Hah, tell me about it. Telling them to stick their offer up their ass was a fabulous experience. Having interviewed for and been accepted by every major in the country, that lot were by far the worst to deal with during the interview process.
What a load of garbage. Accepted by them all eh? Must have been that PMI exam that got you in eh?
If that's how you rejected a job offer I'd reckon they're pretty happy you didn't accept. Clown.