diff -up xorg-server-1.3.0.0/fb/fbtrap.c.jx xorg-server-1.3.0.0/fb/fbtrap.c
--- xorg-server-1.3.0.0/fb/fbtrap.c.jx	2006-11-16 13:01:23.000000000 -0500
+++ xorg-server-1.3.0.0/fb/fbtrap.c	2008-07-24 10:14:16.000000000 -0400
@@ -115,6 +115,9 @@ fbRasterizeTrapezoid (PicturePtr    pPic
     RenderEdge	l, r;
     xFixed	t, b;
     
+    if (!xTrapezoidValid (trap))
+	return;
+
     fbGetDrawable (pPicture->pDrawable, buf, stride, bpp, pxoff, pyoff);
 
     width = pPicture->pDrawable->width;
diff -up xorg-server-1.3.0.0/render/renderedge.c.jx xorg-server-1.3.0.0/render/renderedge.c
--- xorg-server-1.3.0.0/render/renderedge.c.jx	2006-06-06 13:13:55.000000000 -0400
+++ xorg-server-1.3.0.0/render/renderedge.c	2008-07-24 10:13:48.000000000 -0400
@@ -143,6 +143,7 @@ RenderEdgeInit (RenderEdge	*e,
     dx = x_bot - x_top;
     dy = y_bot - y_top;
     e->dy = dy;
+    e->dx = 0
     if (dy)
     {
 	if (dx >= 0)