Unfortunately no...
When I find myself in this situation, however, I just toast all the user in Exchange directly and then run the dbWalker application to clean up the orphaned handlers that result.
not real clean, but it works and can save you some time if you have lots and lots of users to delete.
The crew at AnswerMonkey.net has this on their list of items to address with a snappy tool. Got lots of stuff on my plate, however, so I'm not sure when/if I'll get to this.
Jeff Lindborg
Unity Product Architect/Answer Monkey
Cisco Systems
jlindborg@activevoice.com
http://www.AnswerMonkey.net (new page for Unity support tools and scripts)