表单.post与jquery响应返回相同的页面

Trying to post a form with jquery and the response data is the html from the current page, not the url specified in the function.

<form name="vote_form" class="vote_form" action="vote.php"> 
    <input type="hidden" name="sid" id="sid" value="2056" />
    <input type="submit" name="up" id="up" value="Vote Up" />
    <input type="submit" name="down" id="down" value="Vote Down" /> 
</form>

Here's the jquery

$(document).ready(function() {  
$(".vote_form").submit(function() { return false; });
$("#up, #down").click(function(event) {
    $form = $(this).parent("form");
    $.post($form.attr("action"), $form.serialize() + "&submit="+ $(this).attr("name"), function(data) {
            $('#results').html(data);
        });
    }); 
}); 

For reference if there is an issue here, the .htaccess

Options +ExecCGI
AddHandler php-cgi .php .html .htm .xml
Action php-cgi /cgi-bin/php.cgi

<FilesMatch "^php5?\.(ini|cgi)$">
Order Deny,Allow
Deny from All
Allow from env=REDIRECT_STATUS
</FilesMatch>

#Options +Indexes
Options +FollowSymlinks

RewriteEngine On
RewriteBase /

I read one question here with a similar issue fixed changing URL PROTOCOL from AUTO to URI_REQUEST but I am not using CodeIgnitor or any other framework.

I've basically stripped everything from the page and just using the form and jquery above (vote.php only prints out the $_POST variables - tried with $_REQUEST also).

Basically I'm stumped. Any thoughts?

Have you ever tried alert( $form.attr("action") ) just to be sure you are getting the right thing? And also going to vote.php with your browser?