F-1 resident alien and SS/Medicare Tax withheld?

I turned resident alien since 2010 and pursuing PhD as international graduate student. My employer deducted 6.2% as SS and 1.45% as Medicare tax. I am a bit confused if those taxes apply to me. I am a student (frankly, this is not small money for me). If I am not obliged, is there anyway that I can claim a reimbursement using 1040 or some-other form? I highly appreciate your cooperation. Thank you very much.