diff --git a/src/etc/testcases/taskdefs/optional/junitlauncher.xml b/src/etc/testcases/taskdefs/optional/junitlauncher.xml
index d24421371..3daa397a0 100644
--- a/src/etc/testcases/taskdefs/optional/junitlauncher.xml
+++ b/src/etc/testcases/taskdefs/optional/junitlauncher.xml
@@ -32,6 +32,7 @@
         <fileset dir="../../../../../lib/optional" includes="junit-vintage-engine*.jar"/>
         <fileset dir="../../../../../lib/optional" includes="junit-*.jar"/>
         <fileset dir="../../../../../lib/optional" includes="hamcrest*.jar"/>
+        <fileset dir="../../../../../lib/optional" includes="opentest4j*.jar"/>
     </path>
 
     <path id="junit.engine.jupiter.classpath">
@@ -210,5 +211,64 @@
             </test>
         </junitlauncher>
     </target>
+
+    <target name="test-ant-runtime-lib-custom-location" depends="init">
+        <!-- duplicate the Ant classes into a jar -->
+        <jar destfile="${output.dir}/ant-runtime-duplicated.jar" basedir="${ant.runtime.classes.original.path}"/>
+
+        <junitlauncher>
+            <classpath>
+                <path refid="junit.engine.jupiter.classpath"/>
+                <path refid="junit.engine.vintage.classpath"/>
+                <pathelement location="${build.classes.dir}"/>
+                <!-- our duplicated Ant runtime classes jar, since we
+                exclude the original Ant runtime classes on the fork element
+                by setting includeAntRuntimeLibraries=false -->
+                <pathelement location="${output.dir}/ant-runtime-duplicated.jar"/>
+            </classpath>
+            <testclasses outputdir="${output.dir}">
+                <fileset dir="${build.classes.dir}">
+                    <include name="org/example/**/junitlauncher/**/"/>
+                </fileset>
+                <listener classname="org.example.junitlauncher.Tracker"
+                          outputDir="${output.dir}"
+                          resultFile="${test-ant-runtime-lib-custom-location.tracker}"
+                          if="test-ant-runtime-lib-custom-location.tracker"/>
+                <fork dir="${basedir}" includeAntRuntimeLibraries="false">
+                    <sysproperty key="junitlauncher.test.sysprop.one" value="forked"/>
+                </fork>
+            </testclasses>
+        </junitlauncher>
+    </target>
+
+
+    <target name="test-ant-and-junit-platform-lib-custom-location" depends="init">
+        <!-- duplicate the Ant classes into a jar -->
+        <jar destfile="${output.dir}/ant-runtime-duplicated.jar" basedir="${ant.runtime.classes.original.path}"/>
+
+        <junitlauncher>
+            <classpath>
+                <path refid="junit.engine.vintage.classpath"/>
+                <pathelement location="${build.classes.dir}"/>
+                <!-- our duplicated Ant runtime classes jar, since we
+                exclude the original Ant runtime classes on the fork element
+                by setting includeAntRuntimeLibraries=false -->
+                <pathelement location="${output.dir}/ant-runtime-duplicated.jar"/>
+                <!-- we set includeJUnitPlatformLibraries=false on the fork element
+                    and then explicitly specify a location of the JUnit platform libraries -->
+                <path refid="junit.platform.classpath"/>
+            </classpath>
+            <testclasses outputdir="${output.dir}">
+                <fileset dir="${build.classes.dir}">
+                    <include name="org/example/**/junitlauncher/**/JUnit4SampleTest.class"/>
+                </fileset>
+                <listener classname="org.example.junitlauncher.Tracker"
+                          outputDir="${output.dir}"
+                          resultFile="${test-ant-and-junit-platform-lib-custom-location.tracker}"
+                          if="test-ant-and-junit-platform-lib-custom-location.tracker"/>
+                <fork dir="${basedir}" includeAntRuntimeLibraries="false" includeJUnitPlatformLibraries="false"/>
+            </testclasses>
+        </junitlauncher>
+    </target>
 </project>
 
diff --git a/src/tests/junit/org/apache/tools/ant/taskdefs/optional/junitlauncher/JUnitLauncherTaskTest.java b/src/tests/junit/org/apache/tools/ant/taskdefs/optional/junitlauncher/JUnitLauncherTaskTest.java
index cdae304d2..97a40c184 100644
--- a/src/tests/junit/org/apache/tools/ant/taskdefs/optional/junitlauncher/JUnitLauncherTaskTest.java
+++ b/src/tests/junit/org/apache/tools/ant/taskdefs/optional/junitlauncher/JUnitLauncherTaskTest.java
@@ -19,6 +19,8 @@ package org.apache.tools.ant.taskdefs.optional.junitlauncher;
 
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.BuildFileRule;
+import org.apache.tools.ant.Project;
+import org.apache.tools.ant.util.LoaderUtils;
 import org.example.junitlauncher.jupiter.JupiterSampleTest;
 import org.example.junitlauncher.vintage.AlwaysFailingJUnit4Test;
 import org.example.junitlauncher.vintage.ForkedTest;
@@ -28,6 +30,7 @@ import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 
+import java.io.File;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 
@@ -208,8 +211,8 @@ public class JUnitLauncherTaskTest {
                 throw be;
             }
         }
-        final String exlusionLogMsg = "Excluding JUnit platform libraries";
-        Assert.assertTrue("JUnit platform libraries weren't excluded from classpath", buildRule.getFullLog().contains(exlusionLogMsg));
+        final String exclusionLogMsg = "Excluding JUnit platform libraries";
+        Assert.assertTrue("JUnit platform libraries weren't excluded from classpath", buildRule.getFullLog().contains(exclusionLogMsg));
     }
 
     /**
@@ -234,8 +237,8 @@ public class JUnitLauncherTaskTest {
                 throw be;
             }
         }
-        final String exlusionLogMsg = "Excluding Ant runtime libraries";
-        Assert.assertTrue("Ant runtime libraries weren't excluded from classpath", buildRule.getFullLog().contains(exlusionLogMsg));
+        final String exclusionLogMsg = "Excluding Ant runtime libraries";
+        Assert.assertTrue("Ant runtime libraries weren't excluded from classpath", buildRule.getFullLog().contains(exclusionLogMsg));
     }
 
 
@@ -250,14 +253,75 @@ public class JUnitLauncherTaskTest {
         final String targetName = "test-junit-platform-lib-custom-location";
         final Path trackerFile = setupTrackerProperty(targetName);
         buildRule.executeTarget(targetName);
-        final String exlusionLogMsg = "Excluding JUnit platform libraries";
-        Assert.assertTrue("JUnit platform libraries weren't excluded from classpath", buildRule.getFullLog().contains(exlusionLogMsg));
+        final String exclusionLogMsg = "Excluding JUnit platform libraries";
+        Assert.assertTrue("JUnit platform libraries weren't excluded from classpath", buildRule.getFullLog().contains(exclusionLogMsg));
         Assert.assertTrue("JupiterSampleTest#testSucceeds was expected to succeed", verifySuccess(trackerFile,
                 JupiterSampleTest.class.getName(), "testSucceeds"));
-        Assert.assertTrue("JupiterSampleTest#testFails was expected to succeed", verifyFailed(trackerFile,
+        Assert.assertTrue("JupiterSampleTest#testFails was expected to fail", verifyFailed(trackerFile,
                 JupiterSampleTest.class.getName(), "testFails"));
     }
 
+    /**
+     * Tests that in a forked mode execution, with {@code includeAntRuntimeLibraries} attribute set to false
+     * and with the test classpath explicitly including Ant runtime library jars, the tests are executed successfully
+     *
+     * @throws Exception
+     */
+    @Test
+    public void testAntRuntimeLibsCustomLocation() throws Exception {
+        final String targetName = "test-ant-runtime-lib-custom-location";
+        final Path trackerFile = setupTrackerProperty(targetName);
+        // setup a property that points to the locations of Ant runtime classes.
+        // this path will then be used in target to create a duplicate copied
+        // classes and then will be used as a custom location for Ant runtime libraries
+        final String projectResourceName = LoaderUtils.classNameToResource(Project.class.getName());
+        final File antClassesPath = LoaderUtils.getResourceSource(Project.class.getClassLoader(), projectResourceName);
+        buildRule.getProject().setProperty("ant.runtime.classes.original.path", antClassesPath.getAbsolutePath());
+        // run the target
+        buildRule.executeTarget(targetName);
+        final String exclusionLogMsg = "Excluding Ant runtime libraries";
+        Assert.assertTrue("Ant runtime libraries weren't excluded from classpath", buildRule.getFullLog().contains(exclusionLogMsg));
+        Assert.assertTrue("JupiterSampleTest#testSucceeds was expected to succeed", verifySuccess(trackerFile,
+                JupiterSampleTest.class.getName(), "testSucceeds"));
+        Assert.assertTrue("JupiterSampleTest#testFails was expected to fail", verifyFailed(trackerFile,
+                JupiterSampleTest.class.getName(), "testFails"));
+        Assert.assertTrue("AlwaysFailingJUnit4Test#testWillFail was expected to fail", verifyFailed(trackerFile,
+                AlwaysFailingJUnit4Test.class.getName(), "testWillFail"));
+        Assert.assertTrue("ForkedTest#testSysProp was expected to succeed", verifySuccess(trackerFile,
+                ForkedTest.class.getName(), "testSysProp"));
+
+
+    }
+
+    /**
+     * Tests that in a forked mode execution, with {@code includeAntRuntimeLibraries} and {@code includeJUnitPlatformLibraries}
+     * attributes set to false and with the test classpath explicitly including Ant runtime and JUnit platform library jars,
+     * the tests are executed successfully
+     *
+     * @throws Exception
+     */
+    @Test
+    public void testAntAndJUnitPlatformLibsCustomLocation() throws Exception {
+        final String targetName = "test-ant-and-junit-platform-lib-custom-location";
+        final Path trackerFile = setupTrackerProperty(targetName);
+        // setup a property that points to the locations of Ant runtime classes.
+        // this path will then be used in target to create a duplicate copied
+        // classes and then will be used as a custom location for Ant runtime libraries
+        final String projectResourceName = LoaderUtils.classNameToResource(Project.class.getName());
+        final File antClassesPath = LoaderUtils.getResourceSource(Project.class.getClassLoader(), projectResourceName);
+        buildRule.getProject().setProperty("ant.runtime.classes.original.path", antClassesPath.getAbsolutePath());
+        // run the target
+        buildRule.executeTarget(targetName);
+
+        Assert.assertTrue("Ant runtime libraries weren't excluded from classpath",
+                buildRule.getFullLog().contains("Excluding Ant runtime libraries"));
+        Assert.assertTrue("JUnit platform libraries weren't excluded from classpath",
+                buildRule.getFullLog().contains("Excluding JUnit platform libraries"));
+
+        Assert.assertTrue("JUnit4SampleTest#testBar was expected to pass", verifySuccess(trackerFile,
+                JUnit4SampleTest.class.getName(), "testBar"));
+    }
+
     private Path setupTrackerProperty(final String targetName) {
         final String filename = targetName + "-tracker.txt";
         buildRule.getProject().setProperty(targetName + ".tracker", filename);