Hi there.
I just tried to file my taxes today, but am very confused.
I lived and worked in Massachusetts for 5 months last year.
During this time I earned about $9900 and paid about $1000 in federal taxes and $380 in state taxes. Now my tax preparer told me that I owe another $1400 in state taxes! Is this possible. The rest of the year I lived in Florida, and am back in Florida now again. Here is no state tax, so could this be some kind of mix up? I really hope so. Because I paid about $2000 in federal taxes in Florida too and it seems that I will end up getting only about a $500 return after I pay the owed state tax.
Thanks for your help!

Check the residency requirements for Massachusetts state at the state web site. If you are considered resident of Massachusetts for the year, you will report all your income for 2008.

If you are part year resident of Massachusetts, then you will report only the income during the 5-months period.
From what you have stated, it appears that tax preparer is doing something wrong, are you are part year resident of Massachusetts.
Your U.S. Tax Return: Working or Living in Two or More states (http://taxipay.blogspot.com/2008/06/working-in-two-or-more-states.html)

There HAS to be another state involved, because Florida has NO state income tax.

Please update the post.