>Colon will be a disaster for IPv6. A dot is not, as far as I can see,
>ambiguous either for IPv4 or IPv6.
IPv6 address literals are just a disaster anyway. The general consensus seems
to be that when you use them in URLs and the like (where ports are also
introduced with a colon) the address part is bracketed like so:
http://[3ffe::1:2:3]:80/...
I agree that a dot is unambiguous in a strict technical sense, though I can
see that it might be confusing for both humans and software. Marc's
suggestion of "[10.1.0.14] port=55044 helo=..." seems reasonable enough to me.
p.