Last time I checked I think it was Message button and action button. I dotn think this is something u can change. It is a hardware safety feature in case someone where to totally screw up ur alignment, you wont have to hard reset to get it working again.
Cause once the screen alignment is messed up there is no way to get to the alignment app. (without that hardware shortcut)
P.S. Someone asked about this before, I cant remember what the final verdicted was thoe, search the board.
Nokia 6800 -> Blue Angel -> Wizard -> Hermes -> Kaiser ->
-Palm Treo Pro-
Stock and rocked.