Looks like the richtext.html for your language had a really bad day -- it's a bug in my code too...but I don't speak german, so who knows if it's right or wrong...It's a classic "if a tree fell in the forest" type question --
Somebody likely forgot to switch between wysiwig and code-view mode. Happens to the best of us some days. Happens to the worst of us on most days.
Your error was created when an extra ? slipped into the mix on line 4
change line 4 from
<?php if (!CFG-?>htmleditor)
<?php if (!CFG->htmleditor)
And then for the next big stack of code (until the first </P> after Tilgjengelighet)
change a bunch of > need to be changed to >
change a bunch of < need to be changed to <
change a bunch of " need to be changed to "
There probably are more problems, but those jumped out at me. If it works, tell the language pack people. And give them a firm verbal thrashing.