Under ubuntu 12.10 64bit,chinese is shown as small box when using english as ui language?

For example,I input chinese “设置全局分析参数” within a use case’s ellipse icon,and it is shown fine,but when I "open use case details… ",“设置全局分析参数” will be shown as small boxes in name text box,and if I copy these boxes into chrome’s location bar,it shows as “设置全局分析参数”.And if I switch vp’s UI language to chinese,everything shows fine.So,how to make vp shows chinese consistently when it works under English UI?
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