tmux: enable mouse scrolling in vim instead of history buffer

I have just started using tmux 1.8 recently, after working with screen for a while. After reading things here and there on the internet, I came up with following ~/.tmux.conf However when I open vim and try to scroll with mouse tmux scrolls through its scroll buffer instead of sending the scroll command to vim. Is there a workaround? Following is my config: set-option -g default-shell /bin/bash se