src/Tools/jEdit/lib/Tools/jedit

     CLASSPATH="$(jvmpath "$CLASSPATH")"
     exec "$SCALA_HOME/bin/scalac" $ISABELLE_SCALA_BUILD_OPTIONS -d dist/classes "${SOURCES[@]}"
   ) || fail "Failed to compile sources"
 
   cd dist/classes
-  jar cf "../jars/Isabelle-jEdit.jar" * || failed
+  "$ISABELLE_JDK_HOME/bin/jar" cf "../jars/Isabelle-jEdit.jar" * || failed
   cd ../..
   rm -rf dist/classes
 fi
 
 popd >/dev/null