teatime - 5:24 pm on Mar 28, 2006 (gmt 0)

No, I've had that happen, too, several times. My theory is that, either a human has intervened and un-rejected them, or, the algorithm has 2 steps or makes 2 passes, and that these rejections happen in the first pass.
Just guesses. Maybe Adcenter411 will read this thread and reply.