I was a bit bored tonight so I went out to find a warping player and take a demo of him. Maybe I'm wrong, but IIRC it has been stated here before that (massive?) warping shouldn't be possible with b_antiwarp 1, and that a demo would be required to give some sort of proof. However, that server I was on places no restriction on com_maxfps (could that make the whole thing void?) and my guess is that he got terrible fps, because his ping went up from 20-30 to 100+ when a lot happened around him.
A low com_maxfps could cause warping, since less commands are actually being generated. I will look at a fix, but it may end up causing mispredictions when the framerate gets low.