As stated, there is no way to connect to an IRC server, via a socks 5 server, with auth requirments.
It is doubtful this support with be added for a long time, as 90% of the sockets code will require re-writting.
However, eggdrop is being re-written (being developed as 1.7, and about as much use as a split condom).
stdarg has produced some promising code for use in the sockets department, which will allow for many addons (Basicaly modules, but only for the sockets), like compression of all network traffic, encryption of network traffic, filtering of network traffic and (from what I remember) re-routing of network traffic, all on the fly.