CIDR question

Hi,
      A recent posting on comp.dcom.cisco suggested that you can't
    have a 7-bit subnet. For example, 192.239.0.0 255.255.254.0 should
    be equal to two class C networks, but the two "subnets" would be
    the all zeros and the all ones subnets. Apparently this goes against
    the Host Requirments RFC. Would this be a vaild CIDR route? Thanks....

Erik