Description of problem:
Thunderbird fails to display some of the buttons on the toolbar when envoked using the zh_CN.UTF-8 (my default) 
locale. After the "Get Mail" button is pressed on, the button icon of either "Address Book" or "Forward" would be 
replaced by that of "Get Mail" once the mouse cursor is moved across it. This is not permanent, though, as when I 
moved the mouse to other buttons the changed icon got recovered sometimes. However, it turned out rather 
unpredictable what mouse action could cause the recovery of the icons.

This is only seen with the Chinese locale in use. I tried, in the command line, envoking thunderbird with the 
environmental variable LC_ALL=C then everything works correctly.

I'm using the default Thunderbird GUI theme. 


Version-Release number of selected component (if applicable):
version 2.0.0.12 (20080226)


How reproducible:
In zh_CN.UTF-8 locale, the bug is always reproducible.


Steps to Reproduce:
1. Start Thunderbird in zh_CN.UTF-8 locale;
2. Click the "Get Mail" button to fetch mail;
3. Move the mouse over one of "Address Book" or "Forward".
  

Actual results:
Toolbar icons are displayed incorrectly for the user. The changing of button icons may cause annoyance and 
misguide the user to commit incorrect operations.


Expected results:
The toolbar's buttons should be displayed correctly with any locale.


Additional info: