diff --git a/src/main/org/apache/tools/ant/ComponentHelper.java b/src/main/org/apache/tools/ant/ComponentHelper.java
index 5d8c3db67..0011c19c8 100644
--- a/src/main/org/apache/tools/ant/ComponentHelper.java
+++ b/src/main/org/apache/tools/ant/ComponentHelper.java
@@ -907,9 +907,9 @@ public class ComponentHelper  {
         } else {
             //we are defined, so it is an instantiation problem
             final String classname = def.getClassName();
-            antTask = classname.startsWith("org.apache.tools.ant.");
-            boolean optional = classname.startsWith("org.apache.tools.ant.taskdefs.optional");
-            optional |= classname.startsWith("org.apache.tools.ant.types.optional");
+            antTask = classname.startsWith(MagicNames.ANT_CORE_PACKAGE + ".");
+            boolean optional = classname.startsWith(MagicNames.ANT_CORE_PACKAGE + ".types.optional")
+                    || classname.startsWith(MagicNames.ANT_CORE_PACKAGE + ".taskdefs.optional");
 
             //start with instantiating the class.
             Class<?> clazz = null;
diff --git a/src/main/org/apache/tools/ant/DefaultDefinitions.java b/src/main/org/apache/tools/ant/DefaultDefinitions.java
index 5cc9bb428..d558e4361 100644
--- a/src/main/org/apache/tools/ant/DefaultDefinitions.java
+++ b/src/main/org/apache/tools/ant/DefaultDefinitions.java
@@ -25,7 +25,6 @@ package org.apache.tools.ant;
 public final class DefaultDefinitions {
     private static final String IF_NAMESPACE = "ant:if";
     private static final String UNLESS_NAMESPACE = "ant:unless";
-    private static final String OATA = "org.apache.tools.ant.";
 
     private final ComponentHelper componentHelper;
 
@@ -52,14 +51,14 @@ public final class DefaultDefinitions {
     private void attributeNamespaceDef(String ns) {
         AntTypeDefinition def = new AntTypeDefinition();
         def.setName(ProjectHelper.nsToComponentName(ns));
-        def.setClassName(OATA + "attribute.AttributeNamespace");
+        def.setClassName(MagicNames.ANT_CORE_PACKAGE + ".attribute.AttributeNamespace");
         def.setClassLoader(getClass().getClassLoader());
         def.setRestrict(true);
         componentHelper.addDataTypeDefinition(def);
     }
 
     private void ifUnlessDef(String name, String base) {
-        String classname =  OATA + "attribute." + base;
+        String classname = MagicNames.ANT_CORE_PACKAGE + ".attribute." + base;
         componentDef(IF_NAMESPACE, name, classname);
         componentDef(UNLESS_NAMESPACE, name, classname + "$Unless");
     }
diff --git a/src/main/org/apache/tools/ant/MagicNames.java b/src/main/org/apache/tools/ant/MagicNames.java
index 29bbaeef6..5cf2fa8fa 100644
--- a/src/main/org/apache/tools/ant/MagicNames.java
+++ b/src/main/org/apache/tools/ant/MagicNames.java
@@ -207,11 +207,18 @@ public final class MagicNames {
      */
     public static final String REFID_LOCAL_PROPERTIES = "ant.LocalProperties";
 
+    /**
+     * Name of Ant core package
+     * Value: {@value}
+     * @since Ant 1.10.9
+     */
+    public static final String ANT_CORE_PACKAGE = "org.apache.tools.ant";
+
     /**
      * Name of JVM system property which provides the name of the ProjectHelper class to use.
      * Value: {@value}
      */
-    public static final String PROJECT_HELPER_CLASS = "org.apache.tools.ant.ProjectHelper";
+    public static final String PROJECT_HELPER_CLASS = ANT_CORE_PACKAGE + ".ProjectHelper";
 
     /**
      * The service identifier in jars which provide ProjectHelper implementations.
diff --git a/src/main/org/apache/tools/ant/ProjectHelper.java b/src/main/org/apache/tools/ant/ProjectHelper.java
index a84038a88..5cc7527da 100644
--- a/src/main/org/apache/tools/ant/ProjectHelper.java
+++ b/src/main/org/apache/tools/ant/ProjectHelper.java
@@ -38,17 +38,22 @@ import org.xml.sax.AttributeList;
  */
 public class ProjectHelper {
     /** The URI for ant name space */
-    public static final String ANT_CORE_URI = MagicNames.ANTLIB_PREFIX + "org.apache.tools.ant";
+    public static final String ANT_CORE_URI = MagicNames.ANTLIB_PREFIX
+            + MagicNames.ANT_CORE_PACKAGE;
 
     /** The URI for antlib current definitions */
     public static final String ANT_CURRENT_URI      = "ant:current";
 
     /** The URI for ant specific attributes
      * @since Ant 1.9.1
-     * */
+     */
     public static final String ANT_ATTRIBUTE_URI      = "ant:attribute";
 
-    /** The URI for defined types/tasks - the format is antlib:&lt;package&gt; */
+    /**
+     * The URI for defined types/tasks - the format is antlib:&lt;package&gt;
+     * @deprecated use MagicNames.ANTLIB_PREFIX
+     */
+    @Deprecated
     public static final String ANTLIB_URI = MagicNames.ANTLIB_PREFIX;
 
     /** Polymorphic attribute  */
@@ -57,18 +62,24 @@ public class ProjectHelper {
     /**
      * Name of JVM system property which provides the name of the
      * ProjectHelper class to use.
+     * @deprecated use MagicNames.PROJECT_HELPER_CLASS
      */
+    @Deprecated
     public static final String HELPER_PROPERTY = MagicNames.PROJECT_HELPER_CLASS;
 
     /**
      * The service identifier in jars which provide Project Helper
      * implementations.
+     * @deprecated use MagicNames.PROJECT_HELPER_SERVICE
      */
+    @Deprecated
     public static final String SERVICE_ID = MagicNames.PROJECT_HELPER_SERVICE;
 
     /**
      * name of project helper reference that we add to a project
+     * @deprecated use MagicNames.REFID_PROJECT_HELPER
      */
+    @Deprecated
     public static final String PROJECTHELPER_REFERENCE = MagicNames.REFID_PROJECT_HELPER;
 
     /**
@@ -89,7 +100,7 @@ public class ProjectHelper {
     public static void configureProject(Project project, File buildFile) throws BuildException {
         FileResource resource = new FileResource(buildFile);
         ProjectHelper helper = ProjectHelperRepository.getInstance().getProjectHelperForBuildFile(resource);
-        project.addReference(PROJECTHELPER_REFERENCE, helper);
+        project.addReference(MagicNames.REFID_PROJECT_HELPER, helper);
         helper.parse(project, buildFile);
     }
 
diff --git a/src/main/org/apache/tools/ant/ProjectHelperRepository.java b/src/main/org/apache/tools/ant/ProjectHelperRepository.java
index e87817336..8bee97f91 100644
--- a/src/main/org/apache/tools/ant/ProjectHelperRepository.java
+++ b/src/main/org/apache/tools/ant/ProjectHelperRepository.java
@@ -86,7 +86,7 @@ public class ProjectHelperRepository {
         try {
             ClassLoader classLoader = LoaderUtils.getContextClassLoader();
             if (classLoader != null) {
-                for (URL resource : Collections.list(classLoader.getResources(ProjectHelper.SERVICE_ID))) {
+                for (URL resource : Collections.list(classLoader.getResources(MagicNames.PROJECT_HELPER_SERVICE))) {
                     URLConnection conn = resource.openConnection();
                     conn.setUseCaches(false);
                     registerProjectHelper(getProjectHelperByService(conn.getInputStream()));
@@ -94,13 +94,13 @@ public class ProjectHelperRepository {
             }
 
             InputStream systemResource =
-                ClassLoader.getSystemResourceAsStream(ProjectHelper.SERVICE_ID);
+                ClassLoader.getSystemResourceAsStream(MagicNames.PROJECT_HELPER_SERVICE);
             if (systemResource != null) {
                 registerProjectHelper(getProjectHelperByService(systemResource));
             }
         } catch (Exception e) {
             System.err.println("Unable to load ProjectHelper from service "
-                               + ProjectHelper.SERVICE_ID + " ("
+                               + MagicNames.PROJECT_HELPER_SERVICE + " ("
                                + e.getClass().getName()
                                + ": " + e.getMessage() + ")");
             if (DEBUG) {
@@ -160,7 +160,7 @@ public class ProjectHelperRepository {
     }
 
     private Constructor<? extends ProjectHelper> getProjectHelperBySystemProperty() {
-        String helperClass = System.getProperty(ProjectHelper.HELPER_PROPERTY);
+        String helperClass = System.getProperty(MagicNames.PROJECT_HELPER_CLASS);
         try {
             if (helperClass != null) {
                 return getHelperConstructor(helperClass);
@@ -168,7 +168,7 @@ public class ProjectHelperRepository {
         } catch (SecurityException e) {
             System.err.println("Unable to load ProjectHelper class \""
                                + helperClass + " specified in system property "
-                               + ProjectHelper.HELPER_PROPERTY + " ("
+                               + MagicNames.PROJECT_HELPER_CLASS + " ("
                                + e.getMessage() + ")");
             if (DEBUG) {
                 e.printStackTrace(System.err); //NOSONAR
@@ -191,7 +191,7 @@ public class ProjectHelperRepository {
             }
         } catch (Exception e) {
             System.out.println("Unable to load ProjectHelper from service "
-                    + ProjectHelper.SERVICE_ID + " (" + e.getMessage() + ")");
+                    + MagicNames.PROJECT_HELPER_SERVICE + " (" + e.getMessage() + ")");
             if (DEBUG) {
                 e.printStackTrace(System.err); //NOSONAR
             }
diff --git a/src/main/org/apache/tools/ant/helper/ProjectHelper2.java b/src/main/org/apache/tools/ant/helper/ProjectHelper2.java
index 099cce068..f5785b137 100644
--- a/src/main/org/apache/tools/ant/helper/ProjectHelper2.java
+++ b/src/main/org/apache/tools/ant/helper/ProjectHelper2.java
@@ -1026,7 +1026,7 @@ public class ProjectHelper2 extends ProjectHelper {
             }
             if (extensionPoint != null) {
                 ProjectHelper helper =
-                        context.getProject().getReference(ProjectHelper.PROJECTHELPER_REFERENCE);
+                        context.getProject().getReference(MagicNames.REFID_PROJECT_HELPER);
                 for (String extPointName : Target.parseDepends(extensionPoint, name, "extensionOf")) {
                     if (extensionPointMissing == null) {
                         extensionPointMissing = OnMissingExtensionPoint.FAIL;
diff --git a/src/main/org/apache/tools/ant/listener/CommonsLoggingListener.java b/src/main/org/apache/tools/ant/listener/CommonsLoggingListener.java
index 87b09d63f..96fd274fd 100644
--- a/src/main/org/apache/tools/ant/listener/CommonsLoggingListener.java
+++ b/src/main/org/apache/tools/ant/listener/CommonsLoggingListener.java
@@ -26,6 +26,7 @@ import org.apache.commons.logging.LogFactory;
 import org.apache.tools.ant.BuildEvent;
 import org.apache.tools.ant.BuildListener;
 import org.apache.tools.ant.BuildLogger;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.Task;
 import org.apache.tools.ant.UnknownElement;
@@ -61,11 +62,11 @@ public class CommonsLoggingListener implements BuildListener, BuildLogger {
     /**
      * name of the category under which target events are logged
      */
-    public static final String TARGET_LOG = "org.apache.tools.ant.Target";
+    public static final String TARGET_LOG = MagicNames.ANT_CORE_PACKAGE + ".Target";
     /**
      * name of the category under which project events are logged
      */
-    public static final String PROJECT_LOG = "org.apache.tools.ant.Project";
+    public static final String PROJECT_LOG = MagicNames.ANT_CORE_PACKAGE + ".Project";
 
     /**
      * Construct the listener and make sure that a LogFactory
diff --git a/src/main/org/apache/tools/ant/listener/Log4jListener.java b/src/main/org/apache/tools/ant/listener/Log4jListener.java
index 492b9c886..3720d858a 100644
--- a/src/main/org/apache/tools/ant/listener/Log4jListener.java
+++ b/src/main/org/apache/tools/ant/listener/Log4jListener.java
@@ -20,6 +20,7 @@ package org.apache.tools.ant.listener;
 import org.apache.log4j.Logger;
 import org.apache.tools.ant.BuildEvent;
 import org.apache.tools.ant.BuildListener;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.Target;
 import org.apache.tools.ant.Task;
@@ -36,8 +37,10 @@ public class Log4jListener implements BuildListener {
 
     /**
      * log category we log into
+     * @deprecated use MagicNames.ANT_CORE_PACKAGE
      */
-    public static final String LOG_ANT = "org.apache.tools.ant";
+    @Deprecated
+    public static final String LOG_ANT = MagicNames.ANT_CORE_PACKAGE;
 
     /**
      * Construct the listener
@@ -45,7 +48,7 @@ public class Log4jListener implements BuildListener {
     public Log4jListener() {
         // trigger the log4j initialization (if at all it's not yet initialized)
         @SuppressWarnings("unused")
-        final Logger log = Logger.getLogger(LOG_ANT);
+        final Logger log = Logger.getLogger(MagicNames.ANT_CORE_PACKAGE);
     }
 
     /**
diff --git a/src/main/org/apache/tools/ant/taskdefs/Antlib.java b/src/main/org/apache/tools/ant/taskdefs/Antlib.java
index e2e3bd96f..b7ac88c68 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Antlib.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Antlib.java
@@ -23,8 +23,10 @@ import java.net.URL;
 import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.List;
+
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.ComponentHelper;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.ProjectHelper;
 import org.apache.tools.ant.ProjectHelperRepository;
@@ -77,7 +79,7 @@ public class Antlib extends Task implements TaskContainer {
             // Should be safe to parse
             ProjectHelper parser = null;
             Object p =
-                project.getReference(ProjectHelper.PROJECTHELPER_REFERENCE);
+                project.getReference(MagicNames.REFID_PROJECT_HELPER);
             if (p instanceof ProjectHelper) {
                 parser = (ProjectHelper) p;
                 if (!parser.canParseAntlibDescriptor(antlibResource)) {
diff --git a/src/main/org/apache/tools/ant/taskdefs/BindTargets.java b/src/main/org/apache/tools/ant/taskdefs/BindTargets.java
index a9c160952..763f484ad 100644
--- a/src/main/org/apache/tools/ant/taskdefs/BindTargets.java
+++ b/src/main/org/apache/tools/ant/taskdefs/BindTargets.java
@@ -22,6 +22,7 @@ import java.util.List;
 import java.util.stream.Stream;
 
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.ProjectHelper;
 import org.apache.tools.ant.ProjectHelper.OnMissingExtensionPoint;
 import org.apache.tools.ant.Task;
@@ -72,8 +73,7 @@ public class BindTargets extends Task {
         if (onMissingExtensionPoint == null) {
             onMissingExtensionPoint = OnMissingExtensionPoint.FAIL;
         }
-        final ProjectHelper helper = getProject().getReference(
-                ProjectHelper.PROJECTHELPER_REFERENCE);
+        final ProjectHelper helper = getProject().getReference(MagicNames.REFID_PROJECT_HELPER);
 
         for (String target : targets) {
             helper.getExtensionStack().add(new String[] {extensionPoint,
diff --git a/src/main/org/apache/tools/ant/taskdefs/Classloader.java b/src/main/org/apache/tools/ant/taskdefs/Classloader.java
index fbedf3697..a1a2f15d3 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Classloader.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Classloader.java
@@ -215,7 +215,7 @@ public class Classloader extends Task {
                 if (name == null) {
                     // This allows the core loader to load optional tasks
                     // without delegating
-                    acl.addLoaderPackageRoot("org.apache.tools.ant.taskdefs.optional");
+                    acl.addLoaderPackageRoot(MagicNames.ANT_CORE_PACKAGE + ".taskdefs.optional");
                     getProject().setCoreLoader(acl);
                 }
             }
diff --git a/src/main/org/apache/tools/ant/taskdefs/DefBase.java b/src/main/org/apache/tools/ant/taskdefs/DefBase.java
index 0540f849b..d69406004 100644
--- a/src/main/org/apache/tools/ant/taskdefs/DefBase.java
+++ b/src/main/org/apache/tools/ant/taskdefs/DefBase.java
@@ -20,6 +20,7 @@ package org.apache.tools.ant.taskdefs;
 
 import org.apache.tools.ant.AntClassLoader;
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.types.Path;
 import org.apache.tools.ant.types.Reference;
@@ -145,7 +146,7 @@ public abstract class DefBase extends AntlibDefinition {
             // task we want to define will never be a Task but always
             // be wrapped into a TaskAdapter.
             ((AntClassLoader) createdLoader)
-                .addSystemPackageRoot("org.apache.tools.ant");
+                .addSystemPackageRoot(MagicNames.ANT_CORE_PACKAGE);
         }
         return createdLoader;
     }
diff --git a/src/main/org/apache/tools/ant/taskdefs/ImportTask.java b/src/main/org/apache/tools/ant/taskdefs/ImportTask.java
index 6045fdeef..79685cef0 100644
--- a/src/main/org/apache/tools/ant/taskdefs/ImportTask.java
+++ b/src/main/org/apache/tools/ant/taskdefs/ImportTask.java
@@ -24,6 +24,7 @@ import java.net.URL;
 import java.util.Vector;
 
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.ProjectHelper;
 import org.apache.tools.ant.ProjectHelperRepository;
@@ -138,8 +139,7 @@ public class ImportTask extends Task {
             throw new BuildException("import only allowed as a top-level task");
         }
 
-        ProjectHelper helper = getProject().
-                    getReference(ProjectHelper.PROJECTHELPER_REFERENCE);
+        ProjectHelper helper = getProject().getReference(MagicNames.REFID_PROJECT_HELPER);
 
         if (helper == null) {
             // this happens if the projecthelper was not registered with the project.
@@ -216,12 +216,12 @@ public class ImportTask extends Task {
             // push current stacks into the sub helper
             subHelper.getImportStack().addAll(helper.getImportStack());
             subHelper.getExtensionStack().addAll(helper.getExtensionStack());
-            getProject().addReference(ProjectHelper.PROJECTHELPER_REFERENCE, subHelper);
+            getProject().addReference(MagicNames.REFID_PROJECT_HELPER, subHelper);
 
             subHelper.parse(getProject(), importedResource);
 
             // push back the stack from the sub helper to the main one
-            getProject().addReference(ProjectHelper.PROJECTHELPER_REFERENCE, helper);
+            getProject().addReference(MagicNames.REFID_PROJECT_HELPER, helper);
             helper.getImportStack().clear();
             helper.getImportStack().addAll(subHelper.getImportStack());
             helper.getExtensionStack().clear();
diff --git a/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTask.java b/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTask.java
index 6fd77809b..d67307f7a 100644
--- a/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTask.java
+++ b/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTask.java
@@ -48,6 +48,7 @@ import java.util.stream.Stream;
 
 import org.apache.tools.ant.AntClassLoader;
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.Task;
 import org.apache.tools.ant.taskdefs.Execute;
@@ -1972,7 +1973,7 @@ public class JUnitTask extends Task {
                 // make sure the test annotation are accepted
                 classLoader.addSystemPackageRoot("org.junit");
                 // will cause trouble in JDK 1.1 if omitted
-                classLoader.addSystemPackageRoot("org.apache.tools.ant");
+                classLoader.addSystemPackageRoot(MagicNames.ANT_CORE_PACKAGE);
             }
         }
     }
diff --git a/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTestRunner.java b/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTestRunner.java
index 4370bdcd6..971fa7d47 100644
--- a/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTestRunner.java
+++ b/src/main/org/apache/tools/ant/taskdefs/optional/junit/JUnitTestRunner.java
@@ -49,6 +49,7 @@ import junit.framework.TestResult;
 import junit.framework.TestSuite;
 
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.types.Permissions;
 import org.apache.tools.ant.util.FileUtils;
@@ -85,7 +86,7 @@ public class JUnitTestRunner implements TestListener, JUnitTaskMirror.JUnitTestR
             "junit.textui.TestRunner",
             "java.lang.reflect.Method.invoke(",
             "sun.reflect.",
-            "org.apache.tools.ant.",
+            MagicNames.ANT_CORE_PACKAGE + ".",
             // JUnit 4 support:
             "org.junit.",
             "junit.framework.JUnit4TestAdapter",
diff --git a/src/main/org/apache/tools/ant/types/Description.java b/src/main/org/apache/tools/ant/types/Description.java
index b3c269821..2446d4111 100644
--- a/src/main/org/apache/tools/ant/types/Description.java
+++ b/src/main/org/apache/tools/ant/types/Description.java
@@ -21,6 +21,7 @@ import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.ProjectHelper;
 import org.apache.tools.ant.Target;
@@ -52,7 +53,7 @@ public class Description extends DataType {
      */
     public void addText(String text) {
 
-        ProjectHelper ph = getProject().getReference(ProjectHelper.PROJECTHELPER_REFERENCE);
+        ProjectHelper ph = getProject().getReference(MagicNames.REFID_PROJECT_HELPER);
         if (!(ph instanceof ProjectHelperImpl)) {
             // New behavior for delayed task creation. Description
             // will be evaluated in Project.getDescription()
diff --git a/src/main/org/apache/tools/ant/util/ScriptFixBSFPath.java b/src/main/org/apache/tools/ant/util/ScriptFixBSFPath.java
index 264713640..6e4db9cb2 100644
--- a/src/main/org/apache/tools/ant/util/ScriptFixBSFPath.java
+++ b/src/main/org/apache/tools/ant/util/ScriptFixBSFPath.java
@@ -23,6 +23,7 @@ import java.util.Map;
 
 import org.apache.tools.ant.AntClassLoader;
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 
 
 /**
@@ -31,7 +32,7 @@ import org.apache.tools.ant.BuildException;
  */
 public class ScriptFixBSFPath {
     private static final String UTIL_OPTIONAL_PACKAGE
-        = "org.apache.tools.ant.util.optional";
+        = MagicNames.ANT_CORE_PACKAGE + ".util.optional";
 
     private static final String BSF_PACKAGE = "org.apache.bsf";
     private static final String BSF_MANAGER = BSF_PACKAGE + ".BSFManager";
diff --git a/src/main/org/apache/tools/ant/util/ScriptRunnerCreator.java b/src/main/org/apache/tools/ant/util/ScriptRunnerCreator.java
index 51c0f33df..a53be4277 100644
--- a/src/main/org/apache/tools/ant/util/ScriptRunnerCreator.java
+++ b/src/main/org/apache/tools/ant/util/ScriptRunnerCreator.java
@@ -18,6 +18,7 @@
 package org.apache.tools.ant.util;
 
 import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.Project;
 
 /**
@@ -26,8 +27,7 @@ import org.apache.tools.ant.Project;
  */
 public class ScriptRunnerCreator {
     private static final String AUTO = "auto";
-    private static final String OATAU = "org.apache.tools.ant.util";
-    private static final String UTIL_OPT = OATAU + ".optional";
+    private static final String UTIL_OPT = MagicNames.ANT_CORE_PACKAGE + ".util.optional";
 
     private static final String BSF = "bsf";
     private static final String BSF_PACK = "org.apache.bsf";
diff --git a/src/tests/junit/org/apache/tools/ant/taskdefs/JavaTest.java b/src/tests/junit/org/apache/tools/ant/taskdefs/JavaTest.java
index 9fa0912f5..12654617d 100644
--- a/src/tests/junit/org/apache/tools/ant/taskdefs/JavaTest.java
+++ b/src/tests/junit/org/apache/tools/ant/taskdefs/JavaTest.java
@@ -31,6 +31,7 @@ import java.io.PipedOutputStream;
 
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.BuildFileRule;
+import org.apache.tools.ant.MagicNames;
 import org.apache.tools.ant.input.DefaultInputHandler;
 import org.apache.tools.ant.taskdefs.condition.JavaVersion;
 import org.apache.tools.ant.util.FileUtils;
@@ -346,7 +347,7 @@ public class JavaTest {
 
         Java java = new Java();
         java.setProject(buildRule.getProject());
-        java.setClassname("org.apache.tools.ant.Main");
+        java.setClassname(MagicNames.ANT_CORE_PACKAGE + ".Main");
         java.setArgs("-version");
         java.setFork(true);
         // note: due to the missing classpath it will fail, but the input stream