You might be able to comment on the questions by doing some nasty workaround (yes its nasty, but it can also be fun. :) )using Firebug. I tried removing display:none on the Have Questions or Comments? button for the question, clicked on it, entered some comments, then clicked Submit. Unfortunately, this wont work if you try to put some comments on the solutions. :sigh:
Signature construction in progress. Sorry for the inconvenience.