diff -Naur pycairo-1.8.0-old/cairo/pycairo-surface.c pycairo-1.8.0/cairo/pycairo-surface.c
--- pycairo-1.8.0-old/cairo/pycairo-surface.c	2008-12-10 17:41:16.000000000 +1000
+++ pycairo-1.8.0/cairo/pycairo-surface.c	2008-12-26 19:03:17.000000000 +1000
@@ -310,10 +310,10 @@
 	    return NULL;
 	}
 	Py_DECREF(writer);
-	Py_BEGIN_ALLOW_THREADS
+	/* Py_BEGIN_ALLOW_THREADS */
 	status = cairo_surface_write_to_png_stream (o->surface, _write_func,
 						    file);
-	Py_END_ALLOW_THREADS
+	/* Py_END_ALLOW_THREADS */
     }
     RETURN_NULL_IF_CAIRO_ERROR(status);
     Py_RETURN_NONE;
@@ -505,9 +505,9 @@
     }
     Py_DECREF(reader);
 
-    Py_BEGIN_ALLOW_THREADS
+    /* Py_BEGIN_ALLOW_THREADS */
     is = cairo_image_surface_create_from_png_stream (_read_func, file);
-    Py_END_ALLOW_THREADS
+    /* Py_END_ALLOW_THREADS */
     return PycairoSurface_FromSurface (is, NULL);
 }
 #endif /* CAIRO_HAS_PNG_FUNCTIONS */