This is a test. Here is a link (source contains D%FCrst). If the user moves the mouse over this link, s/he should see http://www.w3.org/People/D%FCrst, but never http://www.w3.org/People/Dürst.

This is another test. Here is a another link (source contains D%C3%BCrst). If the user moves the mouse over this link, s/he should see http://www.w3.org/People/Dürst or http://www.w3.org/People/D%C3%BCrst, but never http://www.w3.org/People/Dürst.