yep, and antivirus programs are overall weak at detecting trojans, further making these 'best scanner' arguments pointless, proving the need for several scanners.
ex. avg antispyware (good for trojans), a squared free (good for trojans), in addition to your antivirus of choice, spybot & hijack this. (I left out adaware since the 2007 version crashes frequently on xp & doesn't work on vista)