[CentOS] IPv6 on Centos 6

>
> Yes, the test system has the default ip6tables, but we always permit icmp:
>

Hmm this is especially weird given the 5.8 systems are working -
otherwise I'd have moved the troubleshooting up to vmware or the
switch next...

Without access to the machines/switches to traffic dump and check in
wireshark you've got me stumped at this point I'm afraid...