you might want to either advise players (or even make it a rule) not to exchange RL info or even regular LJ persona info.
A good idea, I think...I'm unsure of how to word it, though. The best I've got is an addition to the "A player's personal info is hirs..." rule that says, pretty much, that people should be *very* careful about revealing RL info to others. I'm having trouble coming up with more than that that doesn't sound alarmist or condescending (for lack of a better term) to me, though.
I think you're doing pretty good here!
"The Management humbling requests that you do not exchange RL or even LJ identities with your fellow players; interactions should remain character to character only (when possible) in order to help present a sense of mystery and a measure of security. In short, you shouldn't know who is playing the other characters."