diff --git a/src/main/org/apache/tools/ant/AntClassLoader.java b/src/main/org/apache/tools/ant/AntClassLoader.java
index 7d18f1ca8..189351f24 100644
--- a/src/main/org/apache/tools/ant/AntClassLoader.java
+++ b/src/main/org/apache/tools/ant/AntClassLoader.java
@@ -448,7 +448,7 @@ public class AntClassLoader extends ClassLoader implements SubBuildListener, Clo
         if (LoaderUtils.isContextLoaderAvailable()) {
             savedContextLoader = LoaderUtils.getContextClassLoader();
             ClassLoader loader = this;
-            if (project != null && "only".equals(project.getProperty("build.sysclasspath"))) {
+            if (project != null && "only".equals(project.getProperty(MagicNames.BUILD_SYSCLASSPATH))) {
                 loader = this.getClass().getClassLoader();
             }
             LoaderUtils.setContextClassLoader(loader);
diff --git a/src/main/org/apache/tools/ant/taskdefs/Classloader.java b/src/main/org/apache/tools/ant/taskdefs/Classloader.java
index aba8e5c7e..fbedf3697 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Classloader.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Classloader.java
@@ -158,10 +158,10 @@ public class Classloader extends Task {
     public void execute() {
         try {
             // Gump friendly - don't mess with the core loader if only classpath
-            if ("only".equals(getProject().getProperty("build.sysclasspath"))
+            if ("only".equals(getProject().getProperty(MagicNames.BUILD_SYSCLASSPATH))
                 && (name == null || SYSTEM_LOADER_REF.equals(name))) {
-                log("Changing the system loader is disabled by build.sysclasspath=only",
-                    Project.MSG_WARN);
+                log("Changing the system loader is disabled by "
+                        + MagicNames.BUILD_SYSCLASSPATH + "=only", Project.MSG_WARN);
                 return;
             }
 
diff --git a/src/main/org/apache/tools/ant/taskdefs/Javac.java b/src/main/org/apache/tools/ant/taskdefs/Javac.java
index ae7963037..ad4ce2a4c 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Javac.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Javac.java
@@ -1350,9 +1350,9 @@ public class Javac extends MatchingTask {
                                      + destDir
                                      + "\" does not exist or is not a directory", getLocation());
         }
-        if (includeAntRuntime == null && getProject().getProperty("build.sysclasspath") == null) {
-            log(getLocation()
-                + "warning: 'includeantruntime' was not set, defaulting to build.sysclasspath=last; set to false for repeatable builds",
+        if (includeAntRuntime == null && getProject().getProperty(MagicNames.BUILD_SYSCLASSPATH) == null) {
+            log(getLocation() + "warning: 'includeantruntime' was not set, defaulting to "
+                            + MagicNames.BUILD_SYSCLASSPATH + "=last; set to false for repeatable builds",
                 Project.MSG_WARN);
         }
     }
diff --git a/src/tests/junit/org/apache/tools/ant/AntClassLoaderTest.java b/src/tests/junit/org/apache/tools/ant/AntClassLoaderTest.java
index 9aafb9a06..cedeed0aa 100644
--- a/src/tests/junit/org/apache/tools/ant/AntClassLoaderTest.java
+++ b/src/tests/junit/org/apache/tools/ant/AntClassLoaderTest.java
@@ -75,7 +75,7 @@ public class AntClassLoaderTest {
         String extjarstring = buildRule.getProject().getProperty("ext.jar");
         Path myPath = new Path(buildRule.getProject());
         myPath.setLocation(new File(mainjarstring));
-        buildRule.getProject().setUserProperty("build.sysclasspath", "ignore");
+        buildRule.getProject().setUserProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         loader = buildRule.getProject().createClassLoader(myPath);
         String path = loader.getClasspath();
         assertEquals(mainjarstring + File.pathSeparator + extjarstring, path);
@@ -87,7 +87,7 @@ public class AntClassLoaderTest {
         String extjarstring = buildRule.getProject().getProperty("ext.jar.nonascii");
         Path myPath = new Path(buildRule.getProject());
         myPath.setLocation(new File(mainjarstring));
-        buildRule.getProject().setUserProperty("build.sysclasspath", "ignore");
+        buildRule.getProject().setUserProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         loader = buildRule.getProject().createClassLoader(myPath);
         String path = loader.getClasspath();
         assertEquals(mainjarstring + File.pathSeparator + extjarstring, path);
@@ -135,7 +135,7 @@ public class AntClassLoaderTest {
         buildRule.executeTarget("prepareGetPackageTest");
         Path myPath = new Path(buildRule.getProject());
         myPath.setLocation(new File(buildRule.getProject().getProperty("test.jar")));
-        buildRule.getProject().setUserProperty("build.sysclasspath", "ignore");
+        buildRule.getProject().setUserProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         loader = buildRule.getProject().createClassLoader(myPath);
         assertNotNull("should find class", loader.findClass("org.example.Foo"));
         assertNotNull("should find package",
@@ -148,7 +148,7 @@ public class AntClassLoaderTest {
         Path myPath = new Path(buildRule.getProject());
         File testJar = new File(buildRule.getProject().getProperty("test.jar"));
         myPath.setLocation(testJar);
-        buildRule.getProject().setUserProperty("build.sysclasspath", "ignore");
+        buildRule.getProject().setUserProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         loader = buildRule.getProject().createClassLoader(myPath);
         Class<?> foo = loader.findClass("org.example.Foo");
         URL codeSourceLocation =
@@ -164,7 +164,7 @@ public class AntClassLoaderTest {
 
         Path myPath = new Path(buildRule.getProject());
         myPath.setLocation(jar);
-        buildRule.getProject().setUserProperty("build.sysclasspath", "ignore");
+        buildRule.getProject().setUserProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         loader = buildRule.getProject().createClassLoader(myPath);
         Class<?> foo = loader.findClass("org.example.Foo");
 
@@ -188,7 +188,7 @@ public class AntClassLoaderTest {
 
         Path myPath = new Path(buildRule.getProject());
         myPath.setLocation(jar);
-        buildRule.getProject().setUserProperty("build.sysclasspath", "ignore");
+        buildRule.getProject().setUserProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         loader = buildRule.getProject().createClassLoader(myPath);
         PrintStream sysErr = System.err;
         try {
diff --git a/src/tests/junit/org/apache/tools/ant/types/CommandlineJavaTest.java b/src/tests/junit/org/apache/tools/ant/types/CommandlineJavaTest.java
index f26116e08..07afc7b58 100644
--- a/src/tests/junit/org/apache/tools/ant/types/CommandlineJavaTest.java
+++ b/src/tests/junit/org/apache/tools/ant/types/CommandlineJavaTest.java
@@ -53,7 +53,7 @@ public class CommandlineJavaTest {
         if (System.getProperty(MagicTestNames.TEST_ROOT_DIRECTORY) != null) {
             project.setBasedir(System.getProperty(MagicTestNames.TEST_ROOT_DIRECTORY));
         }
-        project.setProperty("build.sysclasspath", "ignore");
+        project.setProperty(MagicNames.BUILD_SYSCLASSPATH, "ignore");
         cloneVm = System.getProperty("ant.build.clonevm");
         if (cloneVm != null) {
             System.setProperty("ant.build.clonevm", "false");