EDIT: actually incorrect use of command blocks, not a bug
Type "testfor @p[ score_password=64,score_password_min=64 ]" into a command block. As long as one player on the server has "password" set to 64, the command block will act like everyone has it set to 64, and output signal even if the closest player to the command block has it set to something else. Video demonstration: http://youtu.be/7XTNHYsGgmg
Well, the Syntax of the commandblock works exactly like that: It will check for the nearest player that has those data sets attached. If you want to check if the nearest player has those things set, I dont know a possible way of doing that :/