multi-release jar test doesn't completely work inside Gump

src/tests/antunit/taskdefs/jar-test.xml

@@ -249,7 +249,7 @@ Main-Class: MyClass
         resource="${output}/META-INF/MANIFEST.MF"/>
   </target>
 
-  <target name="testMultiReleaseJar" description="http://openjdk.java.net/jeps/238">
+  <target name="multiReleaseJarPart1" description="http://openjdk.java.net/jeps/238">
     <!-- Preparation of the 'MultiRelease-Project' -->
     <property name="java8.src"  value="${input}/src/java"/>
     <property name="java9.src"  value="${input}/src/java9"/>
@@ -294,6 +294,17 @@ Main-Class: MyClass
     </jar>
     
     <!-- Now some tests -->
+    <au:assertNestedResourceExists>
+      <zipentry zipfile="${antunit.tmpdir}/mrjar.jar" name="META-INF/versions/9/org/apache/ant/test/MRJarTest.class"/>
+    </au:assertNestedResourceExists>
+    <au:assertNestedResourceExists>
+      <zipentry zipfile="${antunit.tmpdir}/mrjar.jar" name="META-INF/versions/10/org/apache/ant/test/MRJarTest.class"/>
+    </au:assertNestedResourceExists>
+  </target>
+
+  <target name="testMultiReleaseJar" depends="multiReleaseJarPart1"
+          unless="build.sysclasspath.only"
+          description="most of the tests happen in , this target contains the part that cannot be tested insid Gump">
     <loadresource property="valueFrom8">
       <javaconstant name="org.apache.ant.test.MRJarTest.VERSION">
         <classpath>
@@ -308,12 +319,6 @@ Main-Class: MyClass
     	<equals arg1="Java9" arg2="${valueFrom8}"/>
       </or>
     </au:assertTrue>
-    <au:assertNestedResourceExists>
-      <zipentry zipfile="${antunit.tmpdir}/mrjar.jar" name="META-INF/versions/9/org/apache/ant/test/MRJarTest.class"/>
-    </au:assertNestedResourceExists>
-    <au:assertNestedResourceExists>
-      <zipentry zipfile="${antunit.tmpdir}/mrjar.jar" name="META-INF/versions/10/org/apache/ant/test/MRJarTest.class"/>
-    </au:assertNestedResourceExists>
   </target>
 
 </project>