@rchern or anyone else following this sillyness, to be notified by Growl on OS X using the IM client Adium, the "Alias" in account settings must match the @ form on MSO chat:
Which means I show up in the user list as TheUnhandledException instead of "The Unhandled Exception", and when I get the user list working, I'll show up twice... That needs to be figured out
But, this means I can, for now, make Mention events the responsibility of the XMPP client
What I'm loving right now @Sathya is that on my Mac, connected to XMPP via Adium,. when people @TheUnhandledException me, My Mac pops up a Growl notice with yoru message, regardless of what app I'm working in :-)