Display problem by german umlauts "ä, ö, ü, ?"

Hello,

I have following problem with news and faqs:

In the news explorer and news browser iview umlauts couldn´t display. Instead of ä, ö, ü or ß is a square-symbol displayed.

If I open a concrete news or faqs form the list when the umlauts are displayed accurately.

Can you give me some advice?

Best regards

Arnold Gallemann