Version 1.5 (download) features IPv6 support, optional half close on eof, and optional connection reset on SIGINT and SIGTERM. Finally SIGHUP is handled correctly. Boris Nikolaus made most of these changes. Thanks, Boris! Prereleases of 1.5 have been running fine for me for a while now, so I don't expect major problems.
The previous version is 1.4; see the CHANGES for details. Get the gzipped tar file from here. Warning: This version is not thoroughly tested, but I suggest you give it a try.
Even older versions are 1.3, 1.2p1, 1.1.
There is a version 2 in the works which is a completely new implementation. It will feature an elaborate, reusable select loop module, UDP and Unix domain sockets, and lots of options. (The options are handled by a completely over-engineered hyper-generic option handler module. Kind of insane, but after all I'm doing this for fun, right? :-)
Version 2 is far from being complete and progressing very slowly, but I am still hopeful that it will some day reach a state of releasability. Basic functionality works for TCP, but most of the features are not yet implemented. See the usage message if you are curious.