No action in submit

[arunsolo1984]

<form name="content" id="content" action="../cgi-bin/upload.cgi?upload_id=" method="POST" enctype="multipart/form-data" onsubmit="setValueforHidden(this)" target="xupload">

when the user presses the submit button(after form valdiation was over ) i have called the below api.
function StartUpload(f1)
{
var UID = Math.round ( 10000 * Math.random () ) + '0' + Math.round ( 10000 * Math.random() );

f1.action = f1.action.split('?')[0]+'?upload_id='+UID;

win1 = window.open(f1.action.split('upload.cgi')[0]+'upload_status.cgi?upload_id='+UID,'win1','width=320,height=240,left=450,top=250');

win1.window.focus();

return true;
}
After that, the follwoing case get fail to execute.
<?php
if ( isset ( $_REQUEST))
{
//Actions run here...
}