Loading Random XML image

I’ve got external jpgs loading into my flash via XML the same as this:
http://www.kirupa.com/developer/mx2004/xml_flash_photogallery1.htm

However, I want the images to load randomly. So unlike the above tutorial, I want it to load a random image each time the user visits it.

Also, I do not need a next and previous button, but one single button which refreshs the movie with a new random image.

Does anyone know how adjust the actionscript/xml to do this?

thanks.