From the Symantec Site:
"W32.Bugbear@mm is a mass-mailing worm. It can also spread through network shares. It has keystroke-logging and backdoor capabilities. The worm also attempts to terminate the processes of various antivirus and firewall programs.
Because the worm does not properly handle the network resource types, it may flood shared printer resources, which causes them to print garbage or disrupt their normal functionality."
You must be getting the virus threw the network. Someone is infected and is sending garbage to your printer, hence, your spooler gets loaded with junk. You need to find the source of your problem. Check who is connected on your server when the problem occurs and eventually you'll narrow it down to who is infected.
"In space, nobody can hear you click..."
