strange issue while saving forum settings

I was setting up the forum configuration items, turning off calendar and galleries, birthday display etc.. and then *blam*, lost all ability to post. I turned off validation on the button and tried and ran through the debugger to see that  the page was invalid. As I didn't know what data was causing it, I had to restore the db from scratch. This was a non-issue as I am just testing it all, but have you run into anything like this before?