Dear all,
I am a foreign national who is working in the US where I have now tax-exempt status, and received the form 1042-S, after a treaty with my home country
However, prior to my current job I was a graduate student, and earned taxable income from Jan-June 2009, but where another treaty ensures that I get most of the federal taxes back.
My question is as follows: I plan to use 1040-NR. Will it be OK to cite both treaties and file both W-2s? Clearly I cannot use the current tax treaty retroactively, but I just wanted to see if any had any thoughts...
Any input welcome - many thanks!

Unless you give more info about your visa type, when you entered the U.S. your citizenship, what treaties are you referring to, it is not possible to answer your question.

Hi, thanks very much!
My citizenship is Norwegian, and I am now on an H-1B. I entered Aug. 2009. However, before this, from 2003-2009, I was on an F-1.
The current tax-free treaty is W-8BEN, which gives me tax-free income for 2009-2010, but I assume it cannot be used retroactively - however, for my income up until my current job, when I was on F-1 status, I planned to use another tax treaty (whose name I cannot recall right here on top of my head) but which gives me some of the federal tax money that I did pay back.

Many thanks!

You were nonresident for 2003 to 2007. For 2008 and 2009 you are resident and must file resident tax return.
You must pay FICA taxes on income during 2008 and 2009 and do not get any treaty deduction.