not against the rules, provided your website also has it's own content. If it is a made for adsense site , then yes...against the rules. (as far as i am aware) James.
Well, I was chatting the other week with google about both my adsense and adwords accounts, the adwords directing traffic to the site with adsense, and they seemed unperturbed about it. The site does, however, have loads and loads of content and has a purpose other than adsense.
I am doing that on many of my websites. Google does not have a problem with that. Good one Grokodile! That can only happen if you already have high traffic and don't really need to use adwords.