widget form posts to page not found

Does anyone know why a widget form on the front side would show “page not found”? I am posting to $_SERVER[‘PHP_SELF’] with a $_GET variable appended.

Form in Widget Example
<form action=”<?php echo $_SERVER[‘PHP_SELF’]; ?>?action=process” method=”post”>
..fields
</form>
or
<form action=”<?php echo $_SERVER[‘PHP_SELF’]; ?>/index.php?action=process” method=”post”>
..fields
</form>

When the form is submitted, it goes to “page not found”

In the widget code I’m using this:
add_action(‘parse_request’, array(class name, ‘process_submission’));