"what"? Since you have a multiple IPv4+ hosts with the same IPv4 address, how would an IPv4 host communicate with an IPv4+ host?
This is the bit that wasn't in djb's original article AFAIR. My take was that 1.2.3.4 and 1.2.3.4.0.0.0.1 would be the same machine -- or at least allocated to the same entity.