My best guess is that you are editing the wrong php.ini file, but I'm no expert at configuring php on a mac, so I couldn't tell you for sure.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.