Q:

why the split line of tmux within putty shows different（xxxxx， qqqqqq）in these tow cases？

Why the split line of tmux within PuTTY shows different（xxxxx， qqqqqq）in these tow cases？
If I do not set PuTTY any thing（the default "Use font encoding"）, the split line of pane shows like following:

But it can't show Chinese word correctly, so I set PuTTY's Window -> Translation -> Remote character set to UTF-8. Then the split line of pane become to like that:
 
Using “xxx qqqq” seems very ugly.
BTW: echo $LANG shows “zh_CN.UTF-8”
So, in this case, How to show Chinese word correctly with the first split line?

A:

I had the same problem with Putty with character set set to UTF-8.
Launching tmux with -u option did the trick (tmux -u)

