--- src/cairo-qt-surface.cpp.orig	2010-01-13 00:36:11.000000000 +0100
+++ src/cairo-qt-surface.cpp	2010-01-13 00:40:33.000000000 +0100
@@ -1555,7 +1555,10 @@
 _cairo_qpainter_surface_flush (void *abstract_surface)
 {
     cairo_qpainter_surface_t *qs = (cairo_qpainter_surface_t *) abstract_surface;
-    
+
+    if (!qs->p)
+        return CAIRO_STATUS_SURFACE_TYPE_MISMATCH;
+
     QPaintDevice * dev = qs->p->device();
     qs->p->end();
     qs->p->begin(dev);