You have chosen the username "%s".  That username is available, and we
will register it for you, if you wish.

Before you decide, please remember:

    -- Your username will stay with you for your entire career at MIT.
       Once it is registered for you, it CANNOT be changed.

    -- Your username is the address that other users will use to send
       messages and mail to you.  If you have chosen a goofy nickname, you
       may register it, but you will be stuck with it for years to come.