[otrs] WebMail probleme: Can't locate object method _fix_folder_name

Hello, when calling the WebMail paket I get the following error message: Can't locate object method "_fix_folder_name" via package "FileHandle" at /usr/share/otrs/Kernel/cpan-lib/Mail/IMAPTalk.pm line 1051, <PRODUCT> line 1316. I'm trying to check a cyrus imap account. system: OTRS 2.2.4 backport form testing running on a Debian/etch box. Ciao!