Working both in the worlds of SAP and PHP is very rewarding when you are able to have some influence on one world with the other. Joe Haynes, a basis consultant whom I follow on twitter was asking the other day for recommendations on php frameworks. I immediately jumped in and recommended Zend Framework as I have recently started working with it and am very happy with it. I also pointed him in the direction of Paddy and Matthew who both have excellent information on their blogs. Better I might say than the official quick start from Zend.
Looking forward to hearing as update when your project gets going Joe, especially if you get some SAP integration going.
 a basis consultant, if you don’t know the secret technical SAP terms, is the guy who installs and monitors your servers