We have a user that has his blackberry in numlock mode.
With the 123 on the screen.

The blackberry has been security password protected. So he needs to enter this to get back in. Problem is with the blackberry locked he cannot get it out of numlock mode without typing the password. Problem is the password has no numbers and because it is in numlock mode it will not accept it.

We have tried the standard ALT and SHIFT+ALT but it just keeps asking for the unlock password first.

Have you tried taking the battery out?

First like stated above pull the battery out and see if that works if not
I would wipe the BB using JavaLoader yes you will loose all the info that is on there but it should be backed up right since it is on your company IT policy? I guess thats better than a locked up BB