Actually it is pretty easy - as long as you don't touch Enterprise Activation.
Go to the Cingular Web client web site at https://webclient.blackberry.net/Web...ite=mycingular
Set up the Web Client to push your Comcast e-mail to the BlackBerry.
To sync up you Contacts, etc., install the software that came with the BlackBerry - it is called Desktop Manager. Make sure you tell Desktop Manager that you are using the BWC and NOT the enterprise BlackBerry Enterprise Server.