Manny-Calavera

I installed windows 2003 enterprise and all is running fine here, all but my modem. I have a Speedtouch Usb Manta from Alcatel. It work's fine when im connected to the internet, but when i try to disconnect, i allways get a "blue screen of death" with the error message: "BAD_POOL_CALLER". I don't know if it has anything to do with my modem drivers are not Windows 2003 autenticated. I allways get a message telling me that these drivers are for an older windows version. I don't know what to do. Everytime that blue screen apear, i have to press the reset button to get out of there... it's very annoying. Can anyone help me? By the way, i know some people who have Siemens and Octal modems and they don't have this kind of problems with Win 2003.