When net.inet6.ip6.v6only=0 is true (the non-default setting), accepted TCP/IPV6 connections where reported by netstat incorrectly, since they had both the INP_IPV4 and the INP_IPV6 flag set. netstat than tries to print the source and destination address as IPv4 addresses although they are IPv6 addresses. This patch fixes this issue.
This also confuses also squid when using ACLs.
Thanks to kib@ and gjb@ for reporting the issue