Controlling access to external pages via vB credentials

[dontpanic]

In vB 2.x I was able to use this code to control access to a page based on member group.

PHP Code:

<?php
error_reporting(7);

require('./global.php');

if ($bbuserinfo[usergroupid]=="1" or $bbuserinfo[usergroupid]=="3" or $bbuserinfo[usergroupid]=="0") {
      eval("dooutput(\"".gettemplate('newsletter_subscribe_error')."\");");
      }else{        
eval("dooutput(\"".gettemplate('newsletter_subscribe')."\");");
}
exit;

?>

I'm missing something when I try to convert it over....can someone please show me what this should look like to accomplish the same basic goal in vB 3.x?

Thanks!