diff -r 30342f40acbf -r e1bea15f9a39 webengine/osswebengine/WebCore/rendering/RenderSlider.cpp
--- a/webengine/osswebengine/WebCore/rendering/RenderSlider.cpp	Thu Jul 15 19:53:20 2010 +0300
+++ b/webengine/osswebengine/WebCore/rendering/RenderSlider.cpp	Thu Aug 19 10:58:56 2010 +0300
@@ -191,10 +191,12 @@
     style->setDisplay(BLOCK);
     style->setPosition(RelativePosition);
 
-    if (parentStyle->appearance() == SliderVerticalAppearance)
-       style->setAppearance(SliderThumbVerticalAppearance);
-    else if (parentStyle->appearance() == SliderHorizontalAppearance)
-       style->setAppearance(SliderThumbHorizontalAppearance);
+    if(parentStyle) {
+        if (parentStyle->appearance() == SliderVerticalAppearance)
+            style->setAppearance(SliderThumbVerticalAppearance);
+        else if (parentStyle->appearance() == SliderHorizontalAppearance)
+            style->setAppearance(SliderThumbHorizontalAppearance);
+    }
 
     return style;
 }