I would like to collect optional contact information when my users register on the website.  I found the place under Manage Profile Properties to display/hide the fields I want.  Then, in order to display these additional fields, I check Require a valid Profile for Registration.

This works great for a while.  I Logout, hit the register link, and everything I want is displayed.  Unfortunately, when I log in again and go back to the User Settings, I find that Require a valid Profile for Registration has become unchecked again.  Sure enough, when I logout and go to register again, all my optional fields are gone and I'm back to the original register page.

What am I doing wrong?  Can anyone confirm that this is happening to them as well?

Thanks for the suggestion, I'll do that.