So the real issue is that he thinks the blackberry "is quiet and has a pathetic vibrate mode".
His (oddRaisin's) solution is to abandon the blackberry and get a pager. mark*workfire has proposed an alternate solution that will probably solve oddRaisin's issue without changing/adding hardware - why are you complaining?
It's a better solution then just throwing hardware at the problem. I've had a blackberry and understand both the original issue and mark*workfire solution - it's (probably) the best given the limited info that oddRaisin provided (did he try anything, including RTFM to see how to setup different volumes based on the time/situaation?)