void main()
{
   object oPC=GetLastUsedBy();
   object oMe=OBJECT_SELF;
   object oOwner=GetLocalObject(oMe,"oOwner");
   if (oPC!=oOwner)
   { // not allowed to open
      SendMessageToPC(oPC,"You do not own this magical chest and cannot open it!");
      AssignCommand(oPC,ClearAllActions(TRUE));
      AssignCommand(oPC,ActionCloseDoor(oMe));
   } // not allowed to open
}