But what should PHP be used for? From where will you get email adresses.. why not use the builting mail() functions in PHP?
Excuse my ignorance but i realy don't see the need of connecting PHP with Outlook
IF the source of the email adresses is a database somewhere on the web its most likely you should stick to only PHP. If the adress list is a static textfile... you should import it into Outlook.
Forgive our strange counter questions but the question itself is kinda strange
/Fredrik