Control + Left and Control + Right to skip words in terminal

In terminal's ubuntu 12.04  , I'm use to Control + Left and Control + Righ to skip words
but after i installed  tmux v1.6 and go to tmux mode I can not use that key.
So for solve this problem, I just edit my .tmxu.conf (in home directory) by add script below.

set-window-option -g xterm-keys on

 save it  and refresh tmux again. Now it work!