Reminds me of one Computer Science professor I had whose degree was in Philosophy - of course he predated computer science degrees. He is part of the older branch of "self-taught" as opposed to degree trained in programming - it is now rarer for someone new to get into the field at a higher level without formal training.
A CS professor at my school graduated after 2000 with a bachelor's in creative writing. She did do her graduate studies in CS, however. So it's still possible to be a professor without studying the field at an undergraduate level.
However, she certainly had formal training in CS, just not at the undergrad level.
