You will be violating the licence agreement if you distribute user.php or any vB file. My suggestion is to reupload the original user.php file and see if that fixes the problem. If it does, then at least you'll know where the problem is.
It's also possible that your host upgrade PHP to 4.2.0/4.2.1 which also causes a problem similar to this. If that's the case, the only fix is to either upgrade to 2.2.6 or apply the tached files in freddie's post here:
http://www.vbulletin.com/forum/showt...threadid=44820