[kh99]

You should be able to do something like this: create a plugin using hook location parse_templates, and code like this:

ob_start();
include "path/included_file.php";
$included_file = ob_get_contents();
ob_end_clean();

vB_Template::preRegister('template_name', array('included_file' => $included_file));

And then in the ad template, use {vb:raw included_file}. Of oucrse you need to use the actual path and file name, use the right template name for the ad location, and you can change 'included_html' to comething else if you want.