saving password at sign-up

For the most part the set password plugin is working just fine except in the situation where a new user must go back and correct another item on the page; I am finding that they usually do not know to refill the password fields and so there is a problem. It would be nice to have some validation that the field is not completed or a temp save. In this type of situation, the user believes they have successfully submitted their password when in fact they have not. Any suggestions?