SImple banner rotator

[Asia_Expat]

I know this has been covered loads before but I need to be very specific.
I use OpenAds to serve my ads but one of my affiliates is very specific about the way they track referrals. Basically, the way my adserver serves their ads means clicks are not tracked by them and I would not be credited for conversions.

I need to put together a little script that would randomly serve 3 or 4 banners in the same place but NOT alter the code in any way... and should appear in the page source code in exactly this format... It HAS to appear in the page source exactly as follows, for 3 or 4 slightly different instances...

<a href="http://www.example.com" rel="nofollow"><img src="http://www.example.com/images/Banner/text banner/text_L.jpg" alt="" /></a>

Can you suggest a way to do this?

[coopster]

If this code must ALWAYS stay exactly the same ...

<a href="http://www.example.com" rel="nofollow"><img src="http://www.example.com/images/Banner/text banner/text_L.jpg" alt="" /></a>

... then I would likely take the file named in the src attribute and make it a dynamic script where a random image would be pushed back out to the browser. To do so you tell your server to parse that particular file using server-side technology and then code the page.