The Palm USB adaptor does work however. I use the Keyspan PDA adaptor , but I have heard from people using the Palm USB, as well as the Griffin ones and they all work just fine. The Palm is a little more difficult to install as you have to put in just the extensions that support the connector and not the palm stuff. There are several sources for cables now. They also sell special cables for connecting these phones directly to Palms and other neet stuff.
Sprint supports a direct connection to the internet.
The only real problem is that your ISP will probably not let you send email via their SMTP servers unless you are dialed into their service. All the other information below is still accurate and the setup is the same. Thanks to everyone who sent in their experiences and information, James Though the Sprint documentation and web site clearly say that you cannot connect your Mac to the internet via their Digital PCS phones. The reality, as is so often the case when someone tells you that you can't do something with your Mac, is that it is quite easy. They make a PeeCee only sync product, but also offer connectivity kits that should work for the Mac as well since it's just the cable.