Index: /applications/editors/josm/plugins/build-common.xml
===================================================================
--- /applications/editors/josm/plugins/build-common.xml	(revision 34597)
+++ /applications/editors/josm/plugins/build-common.xml	(revision 34598)
@@ -15,4 +15,5 @@
     <property name="josm"                   location="../../core/dist/josm-custom.jar"/>
     <property name="josm.test.build.dir"    location="../../core/test/build"/>
+    <property name="jmockit.jar"            location="../00_core_test_lib/jmockit-1.41.jar"/>
     <property name="error_prone_ant.jar"    location="../00_core_tools/error_prone_ant.jar"/>
     <property name="checkstyle.jar"         location="../00_core_tools/checkstyle/checkstyle-all.jar"/>
@@ -554,4 +555,5 @@
                 <junit printsummary="yes" fork="true" forkmode="once" dir="${basedir}">
                     <jvmarg value="-Dfile.encoding=UTF-8"/>
+                    <jvmarg value="-javaagent:${jmockit.jar}"/>
                     <jvmarg value="--add-modules" if:set="isJava9" unless:set="isJava11" />
                     <jvmarg value="java.activation,java.se.ee" if:set="isJava9" unless:set="isJava11" />