diff -r df79aa33bb74 -r 793a429c63e7 lib/Tools/scalac
--- a/lib/Tools/scalac	Wed Sep 11 23:32:47 2013 +0200
+++ b/lib/Tools/scalac	Thu Sep 12 13:23:54 2013 +0200
@@ -6,7 +6,6 @@
 
 isabelle_admin_build jars || exit $?
 
-CLASSPATH="$(jvmpath "$CLASSPATH")"
 isabelle_scala scalac -Dfile.encoding=UTF-8 \
-  "-Djava.ext.dirs=$(jvmpath "$ISABELLE_JAVA_EXT:$ISABELLE_HOME/lib/classes/ext")" "$@"
+  -classpath "$(jvmpath "$ISABELLE_CLASSPATH")" "$@"