INT B3 - ZIPKEY - FETCH AN ENTRY FROM A PREVIOUS LOOKUP                         
	AH = 7Ah
	BL = case number (0 to one less than value returned in BH by lookup)
Return: AL = ZIPKEY state code
	DX = zipcode region (0-999)
	CL = last two digits of first zipcode in the range (0-99)
	CH = last two digits of last zipcode in the range (0-99)
SeeAlso: AH=78h,AH=79h