INT 67 U - RM386 v6.00 - ???                                                    
	AX = 5DFFh
	???
Return: ???
Note:	RM386 traps this function on the initial transition to protected
	  mode caused by the INT instruction, which means it can not be
	  overridden simply by hooking the interrupt
SeeAlso: AX=5DFDh,AX=5DFEh