I can get a VPN connection on an OSX client using either viscosity or IPSEC over L2TP.
However it seems to be IPv4 only, I don't get assigned an IPv6 address over the VPN.
If I change Viscosity to TAP it will connect but will not DHCP for an Ipv4 or obtain an IPv6 via either RA or DHCPv6, set to TUN it gets an IPv4 address but no V6 address information.
A windows client using the SE-VPN client gets assigned both a IPv4 and IPv6 address.
Server is running on Debian 7 VM, running on a Proxmox host, Proxmox is configured to place all traffic to/from the VM on Vlan 6, SE is bridged to eth0 on the VM.
DHCP/DHCPv6 and RA is done by the router/firewall for this vlan (A UBNT edgerouter lite).