Hi, thanks for all your replies. The problem was caused by the mentioned kernel bug (https://bugzilla.redhat.com/show_bug.cgi?id=321111). Akemi Yagi wrote: > This is a known bug. Please see: > > http://bugs.centos.org/view.php?id=2635 > > It was fixed in 5.2. Do I understand correctly, that it won't be fixed in SL 5.1? A bugfix for RHEL 5.1 exists. Regards --- Jan Schulze - Systemadministration Wilhelm-Schickard-Institut für Informatik Universität Tübingen Raum C309, Sand 14, D-72076 Tübingen Telefon: 07071/29-70 449 Telefon mobil: 0172/73 71 906