Avast free edition did not found this virus into the system: Backdoor.ircbot.ayi
Tecnical information:
Copies itself as usnserv.exe in the Windows System folder.
Drops the file NewYear2008.ZIP in the %Temp% folder.
This .zip contains the file Image027.JPEG_VirusScannedBy-Msn.com, which is a copy of the backdoor.
Adds the value
“Userfile Sharing Server” = usnserv.exe
under the key
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
in the Windows registry to hook system startup.
May connect to a specific IRC channel on a certain IRC server to await remote commands.
Please update avast.
Regards.