Need Help With Coding Make Links In Inframe Open In New Window

[iGuest 3]

I want to use this PHP find and replace tool, but apply it to a java feed from tumblr. Does anyone know if this is possible?
The code for the feed is:

<?php$t = $_GET['tag'] ? '/tagged/' . $_GET['tag'] : '' ;  echo '<script type="text/javascript" src="http://tumblr.Com' . $t . '/js?num=7"></script>';?>

Thanks )
-question by anna
Edited April 7, 2012 by moderator (see edit history)