hmm. I've had a few phone interviews and I frankly think they're kind of pointless. They' should have learnt everything they need from your resume, so getting a 'feel' for you in person seems the next logical step, but if they have any questions arising from your resume, the phone interview is when they'll ask you those questions, before deciding whether or not to bring you in for the interview.
Basically, they will want to hear if you sound professional on the phone (so no umms, and aaahs and such, lol, that's a hard part I find!) and they will also be ready with a list of questions relating to your resume, so be prepared, and have answers for any weak parts in the resume.
Best of luck with your phone interview and jobsearch!