ummm hate to be rude but if you deleted your adelphia account from the Bis then how are you sending email from it?
i have all mail forwarded from comcast to Gmail and all gmail forwarded to my Berry. i set the filter in BIS under my comcast account to not forward to my berry. The gmail HAS the same. do not forward. it gets to you because it is forwarded to your cingular name. hide the icons on your home screen so you only have the Blackberry inbox, this has all incoming and outgoing mail in it. Also set the Cingular address to show your adelphia Name.... like this