Where is the difference with Umlaute on Win versus Mac?

[Tiemo Hollmann TB]

Hello,

I am a little puzzled, but probably it's a Rev beginner question.

I have text fields with german text, including Umlaute and "sz". On Win (IDE
and standalone) everything looks quite normal with Umlaute. But the
standalone on a Mac doesn't shows the Umlaute and sz. It replaces them with
any special signs.  From Webdesign I know this topic and differences
depending on setting the charset like e.g. charset=iso-8859-1. I know
differences between browsers, etc. but where is the difference between Win
and Mac with showing Character Sets? Can I assign a charset to a field or
something like this? I didn't find anything.
 
Any help appreciated
Tiemo