That clown is a tad over paranoid...
The only real issue with devices using ipv6 is that most people become relaxed with security, preferring with ipv4 to do it all on the NAT box, with ipv6 there is no NAT, so if you have 5 machines, you need to configure full security on all. If you're an ISP/OSP/ESP, then you should already have appropriate security via your router and server, just remember though, if using linux you need to use ip6tables -as well as- iptables in your firewall rules script.
There is absolutely NO security risk in exposing any server port to the net, be it dovecot, apache, or bind ... or, whatever.
On Thu, 2011-06-23 at 08:23 +0000, Kārlis Repsons wrote:
Hi Timo, hi all others!
In fact, I've only read one person claiming that IPv6 support opens up "too many backdoors" [1], but anyway, as I intend to run just particular services, please give me your opinion if it's insecure to have a dovecot server, which is accessed through a public IPv6 address... (or note just shortly what else could give a firm ground to such claims...)