You are using a MDEf other that the standard MDEF. Either get a newer version or use the system MDEF. With Appearance, the system MDEF has most of the features you would need. (I think)

Yes, we know the Appearance Manager MDEF supports the wizzy modifier keys that Mercutio has offered for years. We also know that the version of Mercutio we're currently using has some display problems with the new AM but we are using it for a reason. For Mozilla/5.0 we're on the way to adopting AM for most UI stuff but we weren't willing to make it a requirement for the 4.0x generation.

qa contact set to glynn

No longer relevant for 5.0 as we'll be using the Apperance Manager's new improved MDEF instead of Mercutio. Verifying as fixed for old code but noting not relevant for new Seamonkey codebase.