User Registration "Guideline" text box.

The blog and story modules have a "Explanation or submission guidelines" text box which displays usefull information to the user when using that feature. I'd like the user module to have a similar features.

I use the profile module, and I'd like to put a header on that page that says something like: "username, email, and password are required. Allow other fields are optional, and they are publicly viewable." A submissions guidlines text box would be a good place for that.

Thanks!