Wikipedia:irssi is a popular IRC client, but since tg started developing irssi-psyc, it can turn into a native PSYC client.
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Old syntax
irssi-psyc is compliant to the old syntax common with current psyced installations:
git it from here:
git clone git://git.psyc.eu/irssyc
Would be terrific if irssi-otr worked in combination with irssi-psyc. See also OTR encryption, Typing, Icecap, http://www.irssi.org and perlpsyc in general.
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New syntax
Then again, OTR is old-fashioned if you can chat over secure share which is a lot more advanced concerning privacy than OTR.
That's what irssyc is for, it's the new native version of irssi-psyc which uses libpsyc to implement the new syntax.
It's designed to work with the new psycd.
git clone git://git.psyc.eu/irssyc