If you try to enter a internationalized domain name as your "website" in your profile, it will be silently stripped of any non-English characters.
Ex: My webiste is http://linus.unnebäck.se/ but when I try to enter that it saves it as
http://linus.unnebck.se/ when it actually should display
linus.unnebäck.se and link to
http://linus.xn--unnebck-9wa.se/ (or just link with the ä, don't now what is the right thing to do).
As I wrote this post I also noticed that the markup ends the link at the first non-English character aswell, look at the example above.