Fixed width fonts in most countries have characters of the same width. Some countries, however, use Latin characters mixed with wider characters—most notable East Asian countries.
The problem is that when formatting, Gnus assumes that if a string is 10 characters wide, it'll be 10 Latin characters wide on the screen. In these countries, that's not true.
To help fix this, you can set
t. This makes buffer generation slower, but the results will be
prettier. The default value under XEmacs is