diff -r 239f8f451976 -r f19be93909f1 src/Tools/jEdit/src/modes/isabelle-options.xml
--- a/src/Tools/jEdit/src/modes/isabelle-options.xml	Thu Sep 26 16:30:32 2013 +0200
+++ b/src/Tools/jEdit/src/modes/isabelle-options.xml	Thu Sep 26 16:42:18 2013 +0200
@@ -4,6 +4,8 @@
 <!-- Isabelle options mode -->
 <MODE>
   <PROPS>
+    <PROPERTY NAME="commentStart" VALUE="(*"/>
+    <PROPERTY NAME="commentEnd" VALUE="*)"/>
     <PROPERTY NAME="noWordSep" VALUE="_'.?"/>
     <PROPERTY NAME="unalignedOpenBrackets" VALUE="{[(«‹⟨⌈⌊⦇⟦⦃" />
     <PROPERTY NAME="unalignedCloseBrackets" VALUE="⦄⟧⦈⌋⌉⟩›»)]}" />