1. Open the Options dialog, Qt4.
2. Type more and more characters into the name edit of a Qt version.
   The name column will become wider and wider. Thus, the qmake paths don't fit the window anymore but there's no scrollbar to make them visible again:
   
3. Keep typing more characters.
   At some point a scroll bar will appear, but this does not enable showing all the qmake paths:
   

Instead, the scrollbar should appear just when the qmake paths grow out of the window.

If this is a bug in Qt itself, please reassign it.