PLEASE.. Do not try and set any boundaries regarding his use of the blackberry. That is a silly boundary and it is unecessary and means nothing to what you are trying to accomplish. Totally not needed here and would actually hurt the situation because it can be perceived as controlling... etc. etc..
However... STAY OBSERVANT... Yes, it could mean he is communicating witht the OW.. We still need to be observant and get the facts....
You deal with the blackberry issue like we have been telling you to act... YOU are in YOUR OWN WORLD.. Distant.. not too talkative... busy with other things.. not paying attention to him.. (he doesn't THINK you are paying attention)..... matter of fact, maybe YOU should be on your own cell phone more while he is on his..........
Follow the plan.. He needs to WONDER what is up with you and why the different aura you are giving him... Your attitude to him should be.. "you can be on your little blackberry for 24-7.. 365 for all I care.... I have things to do.. ta ta.. talk to you later alligator"
He asks what's up... "nothing.. just busy and have a lot on my mind"...... matter of factly.. and distant.. not rude, not mean...
just in your own little world.. (kinda like he is doing to you and look how it makes YOU feel huh?)
Hold the line here. The blackberry is not a boundary issue. If he wants to play on it while you are watching a movie... let him..you aren't his mommy and able to tell him when he can and can't use his own blackberry) if you don't like it.. then YOU go do something else or go to another room.. (not as if you are angry.. just up and leave the room when he isn't paying attention)