I am using Thunderbird to access IMAP on a dual-stacked host, and for some reason it seems to always choose IPv4 over IPv6. From the commandline I always seem to resolve a IPv6 address for ping/tracert, yet Thunderbird never bothers to try it. I ended up making a v6-only hostname for the IMAP server in order to test.
Is there a hidden option somewhere to set preference of v6 over v4 in Thunderbird?
Ive never seen one, but again I guess I haven't looked either. I assume you're using the latest version?
using Thunderbird 8.0 actually, just upgraded to 9.0.1. It auto-updates now and then, strange that I would be what appears to be quite a bit behind, I didn't bother to check.
Going to switch back to the dual-stack hostname and see what it chooses.
I checked on my win7 and linux machines, and they are all preferring ipv6 talking to a dual-stack server. Don't really see an option to prefer one over another.
See /etc/gai.conf
must have been due to the fact I was running 8.0 since it seems to reliably connect on the v6 address now. Sorry for the noise >:(