For the rest of the article:Spam Trojan Installs Own Anti-Virus Scanner
By Ryan Naraine
October 20, 2006
Veteran malware researcher Joe Stewart was fairly sure he'd seen it all until he started poking at the SpamThru Trojanâ€â€a piece of malware designed to send spam from an infected computer.
The Trojan, which uses peer-to-peer technology to send commands to hijacked computers, has been fitted with its own anti-virus scannerâ€â€a level of complexity and sophistication that rivals some commercial software.
http://www.eweek.com/article2/0,1895,2034680,00.asp