via http://www.aep-emu.de/

ODAMEX is a modified Doom source port available for Windows, Mac, Linux and FreeBSD.

Quote:
Odamex 0.5.4 (r2430)
Odamex 0.5.4 was released on August 9th, 2011.
General Odamex Changes:

  • General bug fixes and code optimizations.
  • Experimental Net Demos.
  • Experimental Unlagged.
  • Improved Zdoom compatibility.
  • Fix death cam bug from 0.5.3.
  • New cl_nobob and sv_allownobob variables to allow weapon bob toggle.
  • Apply Eternity´s "west-facing spawns are silent" vanilla bug.

Odamex Client Changes:

  • Mouse4/Mouse5 back button support.
  • Fix CTF ghost flags.
  • Fix CTF sound origin.
  • Scoreboard improvements.
  • Ability to turn off music system through sound menu/cvar (snd_nomusic).
  • New cvar r_skypalette allows vanilla behavior with invulnerability sphere.
  • Changed r_detail cvar default to 0.
Odamex Server Changes:

  • Fixed a crash that occured on some clients when downloading wads due to oversided packets.
  • co_zdoomphys now also enables two way wallrunning.
  • Optional use of the ZDoom Sound Curve (co_zdoomsoundcurve).
  • Begin removal of -config parameter support in favor of +exec.
  • Changed ctf_flagtimeout to seconds instead of tics, with a default of 10.