client cannot reach ipv6-enabled servers

When EIP is up, you cannot reach ipv6 enabled servers.

samsara 戝 
11080 ◯ : wget http://releases.ubuntu.com/precise/ubuntu-12.04.4-server-amd64.iso                                                                                           
--2014-05-20 18:15:07--  http://releases.ubuntu.com/precise/ubuntu-12.04.4-server-amd64.iso
Resolving releases.ubuntu.com (releases.ubuntu.com)... 2001:67c:1360:8001::19, 91.189.92.163
Connecting to releases.ubuntu.com (releases.ubuntu.com)|2001:67c:1360:8001::19|:80... ^C

By #5274 I see that we're currently routing and blocking ipv6 to avoid leakages, but I wonder if we could somehow avoid this side-effect (by not resolving ipv6 addresses in our dns servers maybe?)

(from redmine: created on 2014-05-20, closed on 2014-06-02, precedes #5588 (closed))