Squrrelmail 1.4.22 and bad displaying czech characters in the imap folder

   Hi there,
   when I copied (and reconstructed) user's email imap folders to a  
new server, I see them like this:
"Kamil &AQw-ern&AP0-/", should be "Kamil Černý" (Czech language).  I  
use Squirrelmail as a imap client, isn't there some configuration in  
the cyrus imap server ?
   I tried 1.4.20 and 1.4.21 versions, problem persists. Interesting  
is, that in the 1.4.10a work all fine :-/
   Thanks for kick to the right way.
   Regards
   J.Karliak.

   SM config test :
SquirrelMail version:	1.4.22
Config file version:	1.4.0
Config file last modified:	13 July 2011 14:12:58
Checking PHP configuration...
     PHP version 5.2.14 OK.
     Running as N/A(N/A) / N/A(N/A)
     display_errors:
     error_reporting: 6143
     variables_order OK: GPCS.
     PHP extensions OK. Dynamic loading is disabled.
Checking paths...
     Data dir OK.
     Attachment dir is the same as data dir.
     Plugins are not enabled in config.
     Themes OK.
     Default language OK.
     Base URL detected as: http://email2.fnhk.cz/mail.1.4.22/src