"M_Epstein"...I have researched this myself before dispersing Office 2K3 in my org last Fall and wasn't able to find anything to do this....Office Resource Kit and Group Policy Office 2K3 ADM Templates do not have the specific policy to disable this. I will do a bit more research to see if there is a way to do this through the registry, but the downside to this is your users may need to be local admins for a registry modification to succeed.
Regards.
~coolsport00