jQuery Validate - check value before remote method is called

jQuery Validate - check value before remote method is called

Hi - I have a username field, that a user may change during an update. There is a remote method validator ( http://jqueryvalidation.org/remote-method/) that will check to see if the new username is available. I also have a hidden field which contains the user's current username. Is it possible to check, during validation, and before the remote method is called, whether the user has actually changed their username? (say for example, if they change their mind, or the name they want is unavailable and want to continue with their original username).

Thoughts or suggestions greatly appreciated.