diff --git a/gfx/thebes/gfxXlibSurface.cpp b/gfx/thebes/gfxXlibSurface.cpp
index 9b5621e35754..34ead5c4ac80 100644
--- a/gfx/thebes/gfxXlibSurface.cpp
+++ b/gfx/thebes/gfxXlibSurface.cpp
@@ -47,6 +47,7 @@
 #include "nsAlgorithm.h"
 #include "nsServiceManagerUtils.h"
 #include "nsIPrefService.h"
+#include "cairo-xlib-xrender.h"
 
 // Although the dimension parameters in the xCreatePixmapReq wire protocol are
 // 16-bit unsigned integers, the server's CreatePixmap returns BadAlloc if
@@ -494,3 +495,10 @@ gfxXlibSurface::FindRenderFormat(Display *dpy, gfxImageFormat format)
 
     return (XRenderPictFormat*)NULL;
 }
+
+XRenderPictFormat*
+gfxXlibSurface::XRenderFormat()
+{
+    return cairo_xlib_surface_get_xrender_format(CairoSurface());
+}
+
diff --git a/gfx/thebes/gfxXlibSurface.h b/gfx/thebes/gfxXlibSurface.h
index 815114ecfb96..f955f219d05c 100644
--- a/gfx/thebes/gfxXlibSurface.h
+++ b/gfx/thebes/gfxXlibSurface.h
@@ -86,6 +86,7 @@ public:
 
     Display* XDisplay() { return mDisplay; }
     Drawable XDrawable() { return mDrawable; }
+    XRenderPictFormat* XRenderFormat();
 
     static int DepthOfVisual(const Screen* screen, const Visual* visual);
     static Visual* FindVisual(Screen* screen, gfxImageFormat format);