I've been here for 5 years, am I exempt from these taxes until I get my H1B? thanks.

(1) no, not if you have been working; and (2) how is it that you think you are going to get an H1b if you have been here for five years and presumably working without paying those taxes?

thanks for the reply, sorry couldnt get back to you earlier.
i was in college and then started working on my opt (jan 03). once my petition for the H1B is approved, do i have to pay medicare and social security taxes or is it after i go abroad to get the official h1b stamp? thanks.

deport illegial aliens

No, you don't have to pay SS and Medicare taxes during your OPT. However, once your H1B approved, you have to pay those taxes.

ignorant americans to a part of the world they have not harassed. hmm. on second thought keep them here.