Cross-Platform connections

Hi everyone, I have a problem I hope someone can help with. I need to be able to access various different databases, (Postgres, Microsoft SQL, DBase IV, and possibly Microsoft Schedule data), on several different servers using PHP/Apache/Linux, through an ODBC connection. I don't even know if this is possible so if anyone has any ideas they'd be much appreciated. Thanks Phil P.S. can you please reply to me personally as I'm no longer on the mailing list (couldn't handle the volume of emails every day!)