I’ve taken the liberty of beating David Ashley to the punch with Debian Etch irssi packages since I just upgraded my machine from Sarge and wanted to clear out as much as possible in the way of pending sysadmin taks in the wake of the warpath of updates and fixes as a result of the distribution upgrade. The Debian patches from 0.8.10 have apparently been committed to the upstream source tree, so these .debs are essentially what you’d get when you compile from source (with the Debian-proper prefixes and such, of course).
With the loose hopes that Google will connect this post to someone that wants them, here you go:
irssi-dev_0.8.11-1etch1_i386.deb