I ran it by Veritas support, and they came back with this:
"This email is to inform you that your case has been assigned to me for further assistance. At this time, there are no documented compatibility issues with Exchange SP2. Regarding the reinstalling of the forms, I have not heard of this, nor have I been able to find documentation related to this.
Currently, according to our compatibility list, Exchange SP2 is fully supported. And, although it does not seem to be necessary to reload the forms, I would recommend doing so anyway as part of good practice."
I have since upgraded to SP2 on the front-end server, the EV server, and one back-end server. As of now, there have not been any problems that I am aware of. If all goes well, I'll do the rest of the back-ends this weekend. I have not reloaded the forms. If it ain't broke, don't fix it.