[Zope] The specified locale "de_CH" is not supported by your system

Hi, I do not exactly know when and how this started to happen, but I can not add any local key in zopes config file anymore. When I do, I get an error: The specified locale "de_CH" is not supported by your system This seems to be related to security upgrades of the Linux used (SuSE 9.1). One of the boxes runs since a couple a monts without a zope restart. If I do zopectrl status I get mentioned error. On an other box I had to comment the local setings out in order to be able to start zope. What could be the reason? And where should I look for a solution? Robert