A New Challenge to Iterate Pages

Hi
I've not come across this one before:

I am trying to scrape this page: http://ukcabins.com/cabins/search/

It all goes well until I want to iterate the page. The 'next' URL gives me what appears to be a command or something, but will not run under screen scraper:
http://ukcabins.com/incs/actions/next_page.php?start=0

In the browser it takes you to the next page of data - in Screen Scraper it does not.

I have tried saving a PHPSESSID but I'm a little clueless here. There seems to be little or any POST data when I run through the proxy server.

I can't see what I am missing here - I'm sure it is very obvious, but I'm stumped.

Hope you can help

Regards

Jason