I have the same problem; I just spoke to "Bobby" at the Turbotax helpdesk. She admitted that this has been a problem, but she didn't know what to do, other than to advise me to send in the state returns by mail. She also said that "you only get a couple of days to e-file State after you e-file Federal", which sounded to me like she didn't really know what she was talking about. And of course then, she made sure I knew that I was going to get a feedback form and I should tell them how "helpful" she was to me..... :(
