[otrs] umlaut in e-mail subject

SuSE 8.0 OTRS 0.5 Beta7 When an e-mail come in with umlaut in subject the auto-reply looks like [Ticket#: 1010030] RE: =?iso-8859-1?Q?Nach_ [...] what can I do? All auto-answers are on Latin-1 iso-8859-1. I think this must be correct, isn't it? (sending client is windows outlook) regards Volker