4th year summer internship dilemma!

There was a job positing for a summer internship, but the requirement is that you must be graduated by May 2011, or else you shouldn't applied. (i think they want ppl to start in September 2011 if they do good during the internship)

Im in 3rd year but with the possibility of graduating in december 2011 (took summer courses) so i applied anyways. on my resume i put the expected graduation date as 2011.

What should i do if they ask, or try to avoid the question? or give rational reasons why i could make it work out?

Thanks guys!