--- a/nashorn/make/build-nasgen.xml	Fri Apr 26 17:35:40 2013 +0200
+++ b/nashorn/make/build-nasgen.xml	Fri Apr 26 22:29:11 2013 +0530
@@ -37,6 +37,7 @@
                 <pathelement location="${basedir}/buildtools/nasgen/dist/nasgen.jar"/>
                 <pathelement path="${basedir}/build/classes"/>
             </classpath>
+            <jvmarg value="-Djava.ext.dirs="/>
             <arg value="${basedir}/build/classes"/>
             <arg value="jdk.nashorn.internal.objects"/>
             <arg value="${basedir}/build/classes"/>