IE6 form submit problem

I have this form that consists of a bunch of submit buttons, each submit 
button implements an OnClick event, and the form also uses onSubmit event. 
The problem I am having is as following:

one of my submit button (say Popup button) actually launches another popup 
window, and the popup window contain another form. I use javascript code 
to submit the (second) form in the popup window and close the popup window 
thereafter. If I only do this once, all the buttons on my first form of 
the original window still work fine. However, if I do this once again, 
after the second form submitted and the popup window closes the second 
time,  the buttons on the first form seem to stop working on IE6, even 
though it works fine under FireFox. I tried the Visual Studios .Net's 
script debugger, I can see all the javascript functions that associated 
with the OnClick and OnSubmit events are fired, however, the form is not 
submitted from the web browser on IE6 even though the return value from 
OnSubmit is true.

I don't have much clue how this could be possible on IE6 since it works 
perfectly well on firefox 2.0. Anyone has suggestions on how I should 
proceed with the debug efforts?

--
Shawn He
Online Technology
Office:858-824-5969 Fax: 858-824-5878
AIM: CivRealtor