I am using Gmail to pull email from my Comcast account (my primary email address), then route it to my Blackberry. I deleted the Comcast account from TMO so that I wasn't getting duplicate messages on my BB. The problem I have now is that I can't send an email from the BB using the 'comcast.net' address. I tried adding the Comcast account back to TMO and blocking messages from going to my BB, but that doesn't seem to have worked.

Any suggestions on how I can send email from BB using the 'comcast.net' account, but without receiving messages from Comcast directly to the BB?

Thanks!

Nope. Allowing you to compose an email from your berry using your @comcast address requires you to verify that it belongs to you. It's a security measure. Otherwise you could easily be impersonated by others... In a nutshell, you need to have the comcast account on your berry in order to use it.

But you can set the default filter for the integrated Comcast account to not forward mail.

Just be aware that replies to email to your Comcast address received via gmail will go out via gmail unless you choose forward instead of reply and then change the Send Using field. Why aren't you receiving the Comcast email directly?

I'd recommend integrating the Comcast email account with BIS and allow the BB to receive email directly. It's a lot less hassle. You'd need to filter the Comcast email via the filters for your gmail account in BIS.