regex: string begins with NEITER http NOR cid NOR mailto

Hello! I have got a big problem: I have html content in $html variable, which contains href, src and background tags. Those tags may contain relative adressess and absolute addressess which begin with http(s): or cid: (mail inline attachements) and mailto: I have also variable $basewwwservername, which contains servername of current server. I have to insert this $basewwwservername into all href,src and background tags which are relative and NOT into absolute. In other words I must preg_replace with some pattern that match for example (src)=(\"|)..and not following WORDS: http|cid|mailto and correct rest of string. Does anybody relief my pain?;-) I've lost at least 3 days (almost 3x24hrs;-) Regards Konrad ------ e-mail: kras26@wp.pl