Dired uses a regular expression to find the beginning of a file name. In a long Unix-style directory listing (‘ls -l’), the file name starts after the date. The regexp has thus been written to look for the date. By default, it should understand dates and times regardless of the language, but if your directory listing has an unusual format, Dired may get confused.
There are two approaches to solving this. The first one involves setting things up so that ‘ls -l’ outputs a more standard format. See your OS manual for more information.
The second approach involves changing the regular expression used by