Hi again.
what i am unclear about is if menu.php, which created the xml on the fly, is called from the results page, or does the results page link directly to detail.php, which just uses the xml generated from menu.php
i have done some testing, and i can pass a URL parameter into a php page to create xml, filtered by the URL parameter, this works fine.
what I am unable to do is then use a php header on the xml creating php page to load the detail page directly from this page.
if you can do this, then the URL parameter should be all you need.