Here is an article that might be of interest to you in what you are trying to accomplish:

http://msdn.microsoft.com/msdnmag/issues/02/08/HTTPFilters/default.aspx

>hello everyone. If I execute
>document.Form1.action="http://csnmxirt01:81/supplies/Orders2.aspx?SubmitClicked=1";
>
>how can i get ?SubmitClicked=1 out of the url. everytime my page is re-submitted it reads this parameter and I only want it read once, then it should go away. thanks for the help.