Could someone explain to me why the following works with the 7110 and the mobile browser, but not with the 6210 or 3330. I am using Nokia Internet Toolkit 3.1. I am new to WAP so any help will be appreciated.

<?php
header("Content-type: text/vnd.wap.wml"
echo ("<?xml version=\"1.0\"?>\n"
echo "<!DOCTYPE wml PUBLIC \"-//WAPFORUM//DTD WML 1.1//EN\"" . " \"http://www.wapforum.org/DTD/wml_1.1.xml\">";
?>

<wml>
<card id="card1" title="PHP WML Test">
<p align="center">
***HelloWAP***<br/>
WAP/PHP/MySQL/Apache<br/>
Program Test:<br/>
</p>
</card>
</wml>

When i run it through the 6210 and 3330 i get the following error "File Format Unknown" and "Unknown File Content".