Howdy folks,
 
Just thought I'd pass along this little article on jaw problems to some of you singers, etc.
 
http://drbenkim.com/articles/jaw-pain-treatment.htm
 
It's not a great article, but it's a quick read that might get you to think about some things.  As someone who knows massage and jaw tension very well, I'm not sure the self-masage mentioned is going to do a lot of good (probably won't hurt either), and I don't think trying to eat more soft foods is necessary, unless you are having severe issues (it's good to give the jaw a little work out); but the connection between the neck muscles and the jaw is really important, especially the sternocleidomastoid (the one you can grip in the front of the neck).  Those and the tongue are going to tighten up together, and while it's harder to work out the jaw and tongue, releasing that big muscle will have a domino effect on the smaller ones.
 
Also, if you are really tight, I've found that if you breathe deeply, and give into the tension, allowing your jaw to tighten as much as it wants, eventually it will settle out.  If you do that on a day when you have vocal rest, it should help you recover quicker (if you don't have vocal rest, it's a good survival mechanism).
 
Hope you don't mind the little dissertation, it just struck me as I read this.
 
Take care.
cam