No he doesn't... I know he already has a script which generates the random image (which is why I didn't provide code for that), but if you read my post slowly (which you might needa do, I tend to waffle

) it's because if you check the source for the page the actual URL to the image is sent to the browser, which would need to be changed somehow - the simplest way being AJAX, of course.
If you want a full AJAX implementation, I'm sure I could rustle up code for that.