Logic Bricks allow same brick-name for multiple bricks.
This causes many problems, one is if you delete a brick thats under another brick with same name - the top one will be deleted.
If u work with states this is a killer - cause u dont see it if the bricks not visible in the actual logicstate!
There are circumstances in wich bricks will automaticly get same names.
see the ATTACHED FILE - remove (X) one of the lower bricks - the upper will be deleted
tested in 2.60 and 2.60a