This is how modern versions of Mozilla and IE behave for some reason - it may have something to do with page history. Changing the name of the form element will clear the value - although that creates new problems, it suggests that renaming the form might work too (usually nobody cares about form names so it's a better solution). Changing the name of the page will do it too, and GET vars count for that (I think). So just changing from POST to GET could solve your problem. Of course, you could always use javascript - I wrote something generic enough to work for just about all forms and javascript1.1 browsers at one point, but don't have it on me right now...