This is a family of Internet worms that use different infection technologies depending on their versions.
There are two "basic" worms: "Lee.a" and "Lee.b".
The former spreads via IRC channels, and the latter uses MS Outlook to send infected e-mails.
Other worm versions are modifications and/or combinations of these original ones.
Automatic Removal: Use antivirus (also check How To Remove section)Startup Optimizer to remove it from startup.