Swipe to decline incoming call not really declining it

[jmdroid]

Call comes in, I'm busy, I swipe to decline the call, the text message reply window comes up, I start to use it (or not) and a few seconds later, the same number rings my phone again. This sometimes repeats a third time. I was convinced (and aggravated) that people were calling me back after having been declined. However, it happened enough that I ran some tests by calling myself and found that the swipe to decline did not send the caller directly to voicemail at all, in fact it kept ringing on the calling end and eventually popped up as a new call on the RAZR again. Eventually the caller is sent to voicemail on maximum rings. I did some searching without success, any ideas?