Version:           4.3.2 (using KDE 4.3.2)
Compiler:          gcc Linux (i686) release 2.6.31.12-desktop-1mnb - Mandriva 2010
OS:                Linux
Installed from:    Mandriva RPMs

Mail Date format in one secondair directory which contains a other directory is different than principal directory and gives bad sort of mail

I use Kontact with in french with date format as dd/mm/yyyy; In my principal directories (input - output) But in one of secondair directory, date list format
is mm/dd/yyyy for some message but not all messages : 
One of was with date 03/02/2010 and now the date is 02/03/2010. If I open the message, date stand in the future 02/03/2010. The same for a other one with date 03/01/2010 and now date is 01/03/2010.
Now may be the problem comes from the messages and not coming from directory. I don't know.