Is this how Diebold cheated?

[Onlooker]

My guess is they would have put in a little piece of code that kicked in like a virus on the morning of November 2, awarding extra votes to Bush, and then deleted itself after the polls closed. So, this leads to a few questions that maybew someone here can answer.

Would this sort of program leave any traces? (I.e., would there be a way to do an undelete.)
Do we have any idea how software is loaed on Diebold machines, e.g., can it be done wirelessly, in which case the software could have been loaded surreptitiously by one of the Repug challengers?
Have the Democrats or anyone tried to get hold of a Diebold machine?
Any thoughts on the matter?