Jackon.. it may still possibly be there or the winlogon.exe might possibly be damaged.

If you look at what the virus actually does.. it attacks exe files. and it mutates to avoid detection each time it infects something..it injects its code into running processes to avoid detection.. and it also lowers system security by attacking certain AV files to avoid detection by the AV.

If you're using Xp and leave system restore turned on for any drives.. you will reinfect your PC.. as AV cannot scan inside system restore.

You might want to grab your windows install disk and try to repair windows.  Might solve your problem if something has gone skew with the AV cleaning the file.