I agree that IPv6 support should have bin a higher priority.
But looking at the big picture Untangle is far from alone and that is the SAD SAD truth.
Most right now have "IPv6 Support" but often it is just addressing the unit and basic route.
When we did sets of hardwares with IPv6 support we even got units that there support where that they could block IPv6. So IPv6 Support is just a so weak description.
But hell as soon as Untangle have IPv6 Support and if they can fix the UTM part as well quite quick i think they could walk in to the segment and take a huge part of it.