I think these references are seen rather like job references. To get an idea of how good an employee you will be. Of course, you probably didn't mean for anyone to answer that question!

Did you do any internships?

ETA:

Or if you did any school projects with some students who are now doing well or who were active in school, or did something notable for any TAs. Any language programs, school trips that had an academic component? Maybe try to think out of the norm of what an "academic reference" might mean in this case if you can't go with a professor, and don't let it appear that it even occured to you to ask a professor [because of course you could have asked any one of them if it had occurred to you right? You would have your pick of several excellent references from any of your professors... at least that is the impression you could give]


Josie