Index: src/scanner.l
===================================================================
--- src/scanner.l	(revision 642)
+++ src/scanner.l	(working copy)
@@ -801,6 +801,14 @@
 					  else
 					    REJECT;
 					}
+<FindMembers>"%{"[^\n]*			{ // Mozilla XPIDL lang-specific block
+					  if (!insideIDL)
+					    REJECT;
+					}
+<FindMembers>"%}"			{ // Mozilla XPIDL lang-specific block end
+					  if (!insideIDL)
+					    REJECT;
+					}
 <FindMembers>{B}*("properties"){BN}*":"{BN}*  { // IDL or Borland C++ builder property 
   					  current->mtype = mtype = Property;
 					  current->protection = protection = Public ;
