I think you are confused to manually remove this trojan.so you can try this:
download two great, free programs: SuperAntispyware Free Edition and Spyware Doctor Starter Edition available @ www.download.com.
Install, update, and run complete scans with both of these programs.
This should remove the trojan.
Normally, Avast can remove most infections, but since this is not a true virus (trojan) this might be causing the problems and a malware/spyware scanner maybe be better equipped to handle this infection.
After these scans, also you must go to an online malware scan and removal @ Trend Micro Housecall to double check. This will take care of your problem.
Good Luck!