--- a/nashorn/buildtools/nasgen/build.xml	Fri Jul 05 19:35:39 2013 +0200
+++ b/nashorn/buildtools/nasgen/build.xml	Mon Jul 08 16:33:50 2013 +0530
@@ -42,7 +42,8 @@
            destdir="${build.classes.dir}"
            classpath="${javac.classpath}"
            debug="${javac.debug}"
-           includeantruntime="false">
+           includeantruntime="false" fork="true">
+      <compilerarg value="-J-Djava.ext.dirs="/>
       <compilerarg value="-Xlint:unchecked"/>
       <compilerarg value="-Xlint:deprecation"/>
       <compilerarg value="-XDignore.symbol.file"/>