I have a BB 8700c with Cingular. I have been invited to chat via BB messenger by a friend w/ T-mobile, but it doesn't seem to work. I understand Cingular claims it doesn't support BB messenger, but I also see that others have made it work. I use BIS, not BES, so I'm wondering if that has something to do with it. Can anyone help?? Thanks!

It doesn't matter what service you use, it should work. I have been using mine for months, both when I was using BIS and now that I am using BES. Did you accept the invitation?

it will work, need to download the program, you can get it at blackberry.com . it should be in the invite from your friend.

You say "it doesn't seem to work."

What specifically is the problem you are having.

I use Messenger every single day and I'm on Cingular.

what are your tcp settings?

Wow. Y'all are magic. Now it works....???? Thanks!

They shouldn't matter. I don't think Messenger uses the WAP APN. It uses the default Blackberry APN.

My understanding (which isn't worth much as I haven't really looked into it) was that BB Messenger basically used the PIN messaging infrastructure so TCP settings shouldn't matter.

Blank, and I've been using BB Messenger on Cingular for quite awhile now. As everyone else stated tcp settings don't matter.

Hope this helps.
Rcbjr.