Special characters work fine. If not, it is a BUG.
No, I suspect that you haven't written the variable definition correctly - you probably miss the equal sign. See images below. Note the Input box, and what it looks like if you click in the editable area of it. Note especially the intial equal sign. http://community.qlik.com/blogs/qlikviewdesignblog/2014/11/24/the-equal-sign