The problem you reported can be solved easily by applying the BindAddress option inside a host-specific block of ssh_config or $HOME/.ssh/config. For example:
Host ipv4host.example.com BindAddress my.local.ip4.addr
Host ipv6host.example.com BindAddress my:local:ip6:addr
You can also put a default IPv4 bindaddress in a "Host *" block at the end of the file then overrride it in the host-specific block for your IPv6 hosts, eg
Host ipv6host.example.com BindAddress my:local:ip6:addr
[other ipv4 hosts]
Host * BindAddress my.local.ip4.addr
-- Darren Tucker (dtucker at zip.com.au) GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4 37C9 C982 80C7 8FF4 FA69 Good judgement comes with experience. Unfortunately, the experience usually comes from bad judgement.
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