Disable USB Devices but leave Cameras enabled?

Hi

we have a script we push out to cumputers tha sets the USBSTOR Start Value to “4” to disable everything except Keyboard / Mice type devices.

However, a number of users require cameras. Is there a value that we can use that will still disable USB Drives but allow Specific devices (i.e. Cameras) to work? I understand that Cameras will probably still be idetified as “Mass Storage Devices” to the OS (Win XP Sp2/SP3) so i doubt there is a solution – but i know there are smarter people out there that I am so please… help if you can 🙂

Jeff