Form controller has ?Stage=Stage attached to it



When $Form shows in a published page, there is ?Stage=Stage attached to the form action url. for example:

<form id="CartForm_CartForm" action="/cart/CartForm/?stage=Stage" method="post" enctype="application/x-www-form-urlencoded">

The Form is a function defined in the page controller by the way.

This is causing problem because one has to login to the site in order to submit the form.

Not sure if any body else knows how to fix it. Currently, i have to use javascript to remove ?stage=Stage in the action attribute.

This is becoming a bit annoying. I have just built a new website and this problem comes up again in the new site.