I have a new Bold and have issues with BBMs from a Sprint user with the same phone and OS. Mine going to him seem to go through fine, although some a little slow, but half of the ones he sends me never go through. Any ideas why?
Are you still having this issue with your BBM's? Does the Sprint user get a check showing the message was sent? I would suggest doing a battery pull on both devices. You can also register the devices by going to Options>Device>Advanced System Settings>Host Routing Table>On the first line, press the Blackberry Menu key and choose Register Now. If you are still having any problems let us know.