I am having the same problem and I have been without email now for over 9 hours. I have logged a ticket twice and on both occasions they have verified that there was a problem but then declared it solved later on. I can't send or receive email and squirrel isn't working for me either.
I signed on with dreamhost about 3 days ago and the domain transfer for the hosting was completed yesterday, so I hope this is just an early teething problem. Very occasionally it will connect but then 30 seconds later its all blocked. Its been quite a frustrating day!
Edit: it was all working fine yesterday and for the first couple of hours today.