Yes, I can confirm that native IPv6 support is available in OpenVPN v2.3-alpha1. That will be one of the major features in the v2.3 release. So please go grab the alpha release and test it out! Please report bugs to either the bug tracker or the openvpn-devel list.
bug tracker:
https://community.openvpn.net/openvpn/newticket (Use your forum login credentials to create a new ticket)
mailng lists:
http://sourceforge.net/mail/?group_id=48978
Download the latest and greatest:
http://openvpn.net/index.php/open-source/downloads.html