[imp] German Umlaut display failed

[Arne]

Hello.

In the MARC-Mailinglist i've found someone with the same problem i've right
know. This question was asked three years ago and there was no unsefull answer.
So here i go again. :-D
If i get a mail with umlaut or characters there're not displayed and replaced
with an question mark (?). If i go to reply this message alle umlaut are
displayed right in the quoted lines. ???:-/

What could be the problem?

Thanks for some hints.

Arne

P.S. Thank you Jan for your support with my last few questions. ;-)