bust out a hex editor and start checking it out. or request the forms to the project. also like bdjuff said, check your process manager. if a program is running an unusually high amount of process it could be suspect. also, alot of good firewall/virus scans will pick up such things.
if you're worried about trojans and backdoors specfically i've seen software firewalls that will ask you everytime ANYthing tries to connect to the internet, so that may be something to look into as well.
what's a matter juicy? afraid your spammer is bugged?
