diff --git a/src/frontends/qt4/GuiCompleter.cpp b/src/frontends/qt4/GuiCompleter.cpp
index b9f8ab4c4e..89696be97f 100644
--- a/src/frontends/qt4/GuiCompleter.cpp
+++ b/src/frontends/qt4/GuiCompleter.cpp
@@ -525,7 +525,7 @@ void GuiCompleter::showPopup(Cursor & cur)
 }
 
 
-void GuiCompleter::hidePopup(Cursor & cur)
+void GuiCompleter::hidePopup(Cursor &)
 {
 	popupVisible_ = false;
 
@@ -786,7 +786,7 @@ void GuiCompleter::setCurrentCompletion(QString const & s)
 			i = n;
 		else
 			i = l;
-		BOOST_ASSERT(0 <= i && i <= n);
+		BOOST_ASSERT(i <= n);
 	}
 
 	// select the first if none was found
diff --git a/src/frontends/qt4/GuiWorkArea.cpp b/src/frontends/qt4/GuiWorkArea.cpp
index e0ccf066ee..0fe721f21a 100644
--- a/src/frontends/qt4/GuiWorkArea.cpp
+++ b/src/frontends/qt4/GuiWorkArea.cpp
@@ -30,6 +30,7 @@
 #include "LyXRC.h"
 #include "MetricsInfo.h"
 #include "qt_helpers.h"
+#include "Text.h"
 #include "version.h"
 
 #include "graphics/GraphicsImage.h"
@@ -239,14 +240,26 @@ GuiWorkArea::GuiWorkArea(Buffer & buffer, GuiView & lv)
 	if (time > 0) {
 		cursor_timeout_.setInterval(time);
 		cursor_timeout_.start();
-	} else
+	} else {
 		// let's initialize this just to be safe
 		cursor_timeout_.setInterval(500);
+	}
 
 	screen_ = QPixmap(viewport()->width(), viewport()->height());
 	cursor_ = new frontend::CursorWidget();
 	cursor_->hide();
 
+	// HACK: Prevents an additional redraw when the scrollbar pops up
+	// which regularily happens on documents with more than one page.
+	// The policy  should be set to "Qt::ScrollBarAsNeeded" soon.
+	// Since we have no geometry information yet, we assume that
+	// a document needs a scrollbar if there is more then four
+	// paragraph in the outermost text.
+	if (buffer.text().paragraphs().size() > 4)
+		setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
+	QTimer::singleShot(50, this, SLOT(fixVerticalScrollBar()));
+
+
 	setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 	setAcceptDrops(true);
 	setMouseTracking(true);
@@ -292,6 +305,13 @@ GuiWorkArea::~GuiWorkArea()
 }
 
 
+void GuiWorkArea::fixVerticalScrollBar()
+{
+	if (!buffer_view_->fullScreen())
+		setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOn);
+}
+
+
 void GuiWorkArea::close()
 {
 	lyx_view_->removeWorkArea(this);
diff --git a/src/frontends/qt4/GuiWorkArea.h b/src/frontends/qt4/GuiWorkArea.h
index e380561df5..7120372341 100644
--- a/src/frontends/qt4/GuiWorkArea.h
+++ b/src/frontends/qt4/GuiWorkArea.h
@@ -148,6 +148,8 @@ private Q_SLOTS:
 	/// close this work area.
 	/// Slot for Buffer::closing signal.
 	void close();
+	/// Slot to restore proper scrollbar behaviour.
+	void fixVerticalScrollBar();
 
 private:
 	friend class GuiCompleter;