I know there is currently thread discussing Yahoo's disregard when using the no follow.
I have my robot.txt file says to disallow the directory containing the ppc pages from all robots. Also in the meta tag of each of those pages is:

<meta name=robots content=noindex,nofollow>

Yet for some reason Yahoo is indexing my pay per click landing pages. Does anyone know how I can stop this?

Google and MSN 's spiders are following directions and not indexing.