INT 21 - LANtastic v4.1+ - SET EXTENDED QUEUE ENTRY
        AX = 5FA9h
        BX = handle of opened queue entry
        DS:SI -> queue entry (see AX=5FA0h)
Return: CF clear if successful
        CF set on error
            AX = error code
Note:   functions exactly the same as AX=5FA1h except the spooled filename is
          also set.  This call supports direct despooling.