I am sure this is a common issue, but i cant find anything via Google.

I create a textfield and start to type... But then Shortcuts seem to be triggered while i am typing and all hell breaks loose. I cant type "q", "w" or "u" for example. (And many more, but i am not in the mood to list them all)
I have to say, this kindof baffles me. Is there really no way to type in text in Krita itself? Do i have to type it in Notepad and copy it every time?

Yes, it's possible to type text directly in Krita... but the feature is kind unstable.

I had problem with previous versions, now I use 2.9.2 on ubuntu 15.04 and the problem disappear.

Do you use the last stable version of Krita ?

I am using KRITA 2.9.8 on Windows 8 (x64)

I'm working on it. Multiline text seems to be fine, it's the artistic text that's broken. It apparently broke just before we tagged the 2.9.8 and I'll make sure there's a fix in the 2.9.9 release that's coming this Wednesday.