I tried to post a reply to the following post, I have a very similar situation:

Hi, I live in CT and work in CT most of the time with a few days in NY and NJ. The company I work for is based in NY. I received W2's for all 3 states. I use Turbo Tax for filing. For example this is my issue: The CT and NY W2 show very similar amounts for total state wages etc, what I made, over $100,000. The NJ W2 just shows exactly what I made in that state, $5300. When I get into my NY state return within TurboTax it calculates all 3 states and displays over $205,000 in total wages even though I only made over $100,000, it's combining all 3 states for total wages. It just seems something is amiss. Any help with be greatly appreciated.
I have the same situation. One thing to note is that we receive a W2 for all states - Do we have to enter each seperately or do we enter one for our resident state and list the local values within there?

When you file in each state it totals each W2 as if that were your full income. NY state requires that 100% of your wages be reported for the entire year, even if you have no worked in NY the eintire year. It says non-residense can use a IT-203-ATT form to enter the number of days you worked in that state. I can't find these in turbo tax.