The newest version of Tmux (1.4, released Dec 2010) has a bunch of fixes and subtle workflow enhancements. Unfortunately Yum still only has 1.3.

You can compile it from source here. I did and got the following errors:

# ./configure
Configured for Linux
# make
cc -DBUILD="\"1.4\"" -std=c99 -D_GNU_SOURCE -D_POSIX_SOURCE -iquote.   -c -o attributes.o attributes.c
In file included from attributes.c:23:
tmux.h:30:19: error: event.h: No such file or directory
In file included from attributes.c:23:
tmux.h:830: error: field 'name_timer' has incomplete type
tmux.h:1032: error: field 'key_timer' has incomplete type
tmux.h:1093: error: field 'event' has incomplete type
tmux.h:1117: error: field 'repeat_timer' has incomplete type
tmux.h:1139: error: field 'identify_timer' has incomplete type
tmux.h:1142: error: field 'message_timer' has incomplete type
make: *** [attributes.o] Error 1

After checking around, I discovered I was missing these two packages:

yum install libevent-devel
yum install ncurses-devel ncurses

Recompile and you should be golden.

Addendum: on a fresh Ubuntu install it’s:

apt-get install libevent-dev
apt-get install libncurses5-dev libncursesw5-dev