INT 2F - ZyXEL ZFAX v3+ - SEND VOICE                                            
	AX = DB21h
	DS:SI -> filename including path (max 128 characters)
	DS:BX -> remote phone number
Return: AX = status (see #03096)
SeeAlso: AX=DB11h,AX=DB20h,AX=DB22h,AX=DB23h,AX=DB24h