According to ClusterXL R80.20 Administration Guide:
IPv6 is the "future" and we would like to start using IPv6 only VLANs (without need to configured dummy IPv4).
What is the reason to have IPv6 for the VLAN if you still have to configure IPv4 ? In our cases IPv4 is not used anywhere, we just have to configure dummy IPv4 because " All interfaces configured with an IPv6 address must also have a corresponding IPv4 address."
This is not the only limitation of IPv6:
From IPv6 support FAQ:
Do some know when we can expect the full support of IPv6 within ClusterXL?
AFAIK, this wasn't changed in R80.30.