Fixed-width font on Gmail 2

Update: As of March 2009, this doesn't work anymore. But here is updated fixed width font trick for Gmail

After the latest update to Gmail (you know you have the new version because a "Older version" link appears on the upper right corner, and the UI changes slightly) , almost all tweaks ceased to work. This includes the custom CSS for fixed width font.

So, here is the trick again, updated to the new version (you should include this into the userContent.css file under <your firefox profile>/chrome/ directory):

@-moz-document domain(mail.google.com)
{
    /* GMail messages and textarea should use fixed-width font */
    .ArwC7c, .iE5Yyc {
        font-family: MonoSpace !important; 
        font-size: 9pt !important; 
    }
}