diff --git a/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/makefile b/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/makefile
index 289d106bf2e..21b0f89a179 100644
--- a/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/makefile
+++ b/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/makefile
@@ -27,7 +27,7 @@ LIBPATH = \
 
 LDFLAGS = \
           $(LONG_NAME_PROBLEM_LDFLAGS) \
-          $(CGAL_LDFLAGS) \
+          $(CGAL_QT_LDFLAGS) \
           -lCGALQt
 
 
@@ -35,7 +35,7 @@ LDFLAGS = \
 #                    target entries
 #---------------------------------------------------------------------#
 
-all: min_ellipse_2
+all: min_quadrilateral_2
 
 Qt_widget_toolbar$(OBJ_EXT): Qt_widget_toolbar.C Qt_widget_toolbar.moc
 	$(CGAL_CXX) $(CXXFLAGS) $(OBJ_OPT) Qt_widget_toolbar.C
@@ -43,17 +43,19 @@ Qt_widget_toolbar$(OBJ_EXT): Qt_widget_toolbar.C Qt_widget_toolbar.moc
 Qt_widget_toolbar.moc: Qt_widget_toolbar.h
 	$(QT_MOC) -o Qt_widget_toolbar.moc $<
 
-min_ellipse_2.moc: min_ellipse_2.C Qt_widget_toolbar$(OBJ_EXT) 
-	${QT_MOC} -o min_ellipse_2.moc min_ellipse_2.C
+min_quadrilateral_2.moc: min_quadrilateral_2.C Qt_widget_toolbar$(OBJ_EXT) 
+	${QT_MOC} -o min_quadrilateral_2.moc min_quadrilateral_2.C
 
-min_ellipse_2$(OBJ_EXT): min_ellipse_2.C min_ellipse_2.moc
-	$(CGAL_CXX) $(CXXFLAGS) $(OBJ_OPT) min_ellipse_2.C
+min_quadrilateral_2$(OBJ_EXT): min_quadrilateral_2.C min_quadrilateral_2.moc
+	$(CGAL_CXX) $(CXXFLAGS) $(OBJ_OPT) min_quadrilateral_2.C
 
-min_ellipse_2$(EXE_EXT): min_ellipse_2$(OBJ_EXT)
-	$(CGAL_CXX) $(EXE_OPT)min_ellipse_2 min_ellipse_2$(OBJ_EXT) \
+min_quadrilateral_2$(EXE_EXT): min_quadrilateral_2$(OBJ_EXT)
+	$(CGAL_CXX) $(EXE_OPT)min_quadrilateral_2 min_quadrilateral_2$(OBJ_EXT) \
 	 Qt_widget_toolbar$(OBJ_EXT) $(LDFLAGS)
 
-clean: min_ellipse_2.clean
+clean: min_quadrilateral_2.clean \
+       Qt_widget_toolbar.clean \
+       Qt_widget_toolbar_views.clean
 
 #---------------------------------------------------------------------#
 #                    suffix rules
diff --git a/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/min_quadrilateral_views.h b/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/min_quadrilateral_views.h
index 6675c2c6659..7cf7c7606c0 100644
--- a/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/min_quadrilateral_views.h
+++ b/Packages/Qt_widget/demo/Qt_widget/Min_quadrilateral_2/min_quadrilateral_views.h
@@ -14,9 +14,9 @@ template <class R>
 class Qt_view_show_parallelogram : public CGAL::Qt_widget_view
 {
 public:
-  typedef R::Point_2	Point;
-  typedef R::Segment_2	Segment;
-  typedef R::Line_2	Line;
+  typedef typename R::Point_2	Point;
+  typedef typename R::Segment_2	Segment;
+  typedef typename R::Line_2	Line;
 
 
   typedef CGAL::Polygon_traits_2< R>			    Traits;
@@ -60,9 +60,9 @@ template <class R>
 class Qt_view_show_strip : public CGAL::Qt_widget_view
 {
 public:
-  typedef R::Point_2	Point;
-  typedef R::Segment_2	Segment;
-  typedef R::Line_2	Line;
+  typedef typename R::Point_2	Point;
+  typedef typename R::Segment_2	Segment;
+  typedef typename R::Line_2	Line;
 
 
   typedef CGAL::Polygon_traits_2< R>			    Traits;
@@ -103,9 +103,9 @@ template <class R>
 class Qt_view_show_rectangle : public CGAL::Qt_widget_view
 {
 public:
-  typedef R::Point_2	Point;
-  typedef R::Segment_2	Segment;
-  typedef R::Line_2	Line;
+  typedef typename R::Point_2	Point;
+  typedef typename R::Segment_2	Segment;
+  typedef typename R::Line_2	Line;
 
 
   typedef CGAL::Polygon_traits_2< R>			    Traits;
@@ -150,7 +150,7 @@ template <class R>
 class Qt_view_show_points : public CGAL::Qt_widget_view
 {
 public:
-  typedef R::Point_2	Point;
+  typedef typename R::Point_2	Point;
   
   Qt_view_show_points(std::list<Point> *pl){list_of_points = pl;};