Used by the routines at 30575 and 30627. Holds either the address of the second byte of the entry in the phone message table at 27467 or 27506 that corresponds to the phone that Sam is calling (if the person on the other end has a message for him) or picking up a call from, or the address of the final byte of the phone table at 27506 (if the person Sam's calling has no message to give); this address contains the number of the message corresponding to the name that Sam must give in order to receive the telephone message, or 0 if no name is required to receive the message, or 255 if the person Sam's calling will respond with message 46 (I DUNNO NO {name}).