Suggestion needed please!!

I am in H1b in a university now, my I-140 got approved in Oct/2005 based on NIW and I-485 pending. Now I have a chance to go back to school(the same one I work for), and I am offered a RA +tuition coverage. But International office told me I can's use my H1b to accept this RA because H1b is job specific. Anyone here know what should I do under this circumstances?Is there a way I can start my study without waiting for several years?

Thanks a million.