Get italics and full colour support in vim in tux. tmuxcolours.sh installs the other two files with arcane neckbeard magic.

tmux.conf

set -g default-terminal "tmux-256color"

tmux.terminfo

# A screen-256color based TERMINFO that adds the escape sequences for italic.
# run to add to term db: tic tmux.terminfo
tmux|tmux terminal multiplexer,
  ritm=\E[23m, rmso=\E[27m,
  sitm=\E[3m, smso=\E[7m,
  use=screen,

tmux-256color|tmux with 256 colors,
  ritm=\E[23m, rmso=\E[27m,
  sitm=\E[3m, smso=\E[7m,
  use=screen-256color,

tmuxcolours.sh

#!/bin/sh

# Adds screen-256 based TERMINFO with italic support.
tic -x xterm-256color.terminfo
tic -x tmux.terminfo

xterm-256color.terminfo

# A xterm-256color based TERMINFO that adds the escape sequences for italic.
xterm-256color|xterm with 256 colors and italic,
  ritm=\E[23m, sitm=\E[3m,
  use=xterm-256color,