It is straight forward to enable IPv6 on any linux system, since the latest kernel support it very well. This document is more relevant for Redhat linux but the idea is same for all.
Make sure the ipv6 support is not disabled in kernel
Comment out the following line in /etc/modprobe.conf if existing.
#alias ipv6 off
#alias net-pf-10 off
Enable IPv6 networking:
Configure the IPv6 address:
edit /etc/sysconfig/network-scripts/ifcfg-eth0 (or bond0 for bond interfaces, ipv6 works as expected with bond interface as well)
Just restart network and you will be able to see the IPv6 address.
Incase if the ipv6 module doesnt exist in kernel, just do a modprobe:
# modprobe -a ipv6
Almost all softwares in linux works with IPv6,
For apache add the listen address to ipv6 address and enable name virtual host for ipv6 address if required.
You can test your ipv6 connectivity by:
$ ping6 ipv6.google.com