my tmux is cvs. You can just comment out the options that fail, but I recommend getting a newer release. It builds really painlessly.
Edit: 1.1 package: http://ftp.us.debian.org/debian/pool/main/t/tmux/tmux_1.1-1_...
Some commands are still not working (pane-active-border-bg and capture-pane, it seems) but I can take a closer look at those after playing with it for a while and getting comfortable.