The problem could be that even with ipv6 disabled many softwares still request AAAA records, you can double check with tcpdump or wireshark:
apt-get source xxx DNS AAAA archive.ubuntu.com firefox http://google.com DNS A google.com cf bug: 80571 ** Changed in: Ubuntu Assignee: (unassigned) => didier Status: Unconfirmed => In Progress ** Changed in: Ubuntu Status: In Progress => Needs Info -- DNS Resolves everything to 1.0.0.0 intermittently on some ADSL Routers https://launchpad.net/bugs/81057 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
