When I have a validater set on a text box, like an email address, and I put in an incorrect format, I get the error message on the page that tells me it's invalid. But once I go back and correct it and leave focus of the text box, that error message stays on the screen. How do I get it to go away? I know that the validation is correct, because if I put in a correctly formatted email address the first time, I don't get the error message.