WordPress with one database, same domain, two identical installation on two different machine/network(ipv4/ipv6)

Here is the case:

I have already wordpress/blog installation running on httpd with ipv4.(with no ipv6 enabled).
I want everyone with native ipv6 be able accesing my blog.
I have one server already connected to ipv6 via he.net tunnel brokers on different region.

It’s also have httpd listen on both ipv4/ipv6.

So here’s what i have done.

    * I made a backup of wordpress installation on original server.
$ tar cjf wordpress.tar.bz2 wordpress
    * Copy and extract  wordpress backup to ipv6 enabled
server.(in my case it's extracted on /var/www/html/)
$ tar xjf wordpress.tar.bz2
    * Edit wp-config.php

since wordpress using database on original server. I have to create one user, that can access the database from network.(i’m not going to explain how to do it, it’s not beyond this article scope).

define('DB_NAME', 'database');
define('DB_USER', 'user');
define('DB_PASSWORD', 'password');
define('DB_HOST', 'ip of original machine');
define('DB_CHARSET', 'utf8');
define('DB_COLLATE', '');
    * Create virtualhost on httpd, same as original server.