DoomlordVekk: Now, if DOCSIS ran within PPP, that would be a different kettle of fish.
Are you able give us an estimate as to when TelstraClear will be offering native IPv6 over its DSL network? From your post, it appears that IPv6 is ready to go on TelstraClear's PPPoA/DHCP backend.
As an interim measure, are there any plans to offer a 6in4 tunnel service with real v6 addresses from 2001:4402::/32? In other words, something without the terrible routing problems experienced by 6to4's 2002::/16 address range.
HE tunnels can and do work but they probably won't get you to where you want to be, nor in a latency friendly manner.
A tunnel provided to an IPS's own customers shouldn't increase latency too much.