diff --git a/vars/tester.groovy b/vars/tester.groovy
index 98191e1..68d9ec9 100644
--- a/vars/tester.groovy
+++ b/vars/tester.groovy
@@ -50,7 +50,8 @@ private def getJunitCmdTemplate(String capellaProductPath, String applicationPar
   return "sleep 10 && " +
     "java " +
       "${jacocoParameters}" +
-      "-Xms1024m -Xmx3500m -XX:+CMSClassUnloadingEnabled -ea " +
+      "-Xms1024m -Xmx3500m -XX:+CMSClassUnloadingEnabled " +
+      "-ea -da:org.eclipse.emf.common.util.URI " + // bug GMF 438712
       "-Declipse.p2.data.area=@config.dir/../p2 " +
       "-Dfile.encoding=Cp1252 " +
       "-classpath ${capellaPath}/plugins/org.eclipse.equinox.launcher_*.jar org.eclipse.equinox.launcher.Main " +