Magento Admin Category Page Uncaught TypeError: Cannot call method 'split' of undefined

I just upgraded from Magento 1.4.0.1 to 1.7.0.2. In the admin, on the category page, I cannot save the category. I'm not sure of the problem, but when I check Chrome Developer Tools, I see a javascript error: Uncaught TypeError: Cannot call method 'split' of undefined categorySubmit onclick I'll provide access to my staging site for you to fix it, or if it's simple enough, instructions on how to fix it myself. Regardless, I'll need instructions on how to repeat the fix so I can do it myself on Production. The winning bid will be one that can answer the following: "I know how to fix the bug preventing your categories from saving in the admin because ..." (and please give your credentials on why you'll know how to fix this. Thanks!