Hrm... I think you might actually have it right.
I _do_ have a CompactFlash reader, it's a PCMCIA card I use to pull the 256MB CF card out of the digital camera and move images off quicker than USB with and such. (And I never forget the card, unlike that damned cable.)

This one is by SanDisk, but I haven't a clue who actually manufactures it... just threw a piece of CF in the slot, read files and such, and then looked to see if the check.exe file is around. Still not there, although sigverif still reports it. (Minus any details about the file other than the path to it.)

I'm starting to think this could be a stream perhaps...
Will prolly dig deeper on it tomorrow - gonna hit the books some more.
Thanks for the imput - will keep all interested posted on my findings.
Kyrka