diff --git a/src/glx.xml b/src/glx.xml
index 5fedb7b..0f09b28 100644
--- a/src/glx.xml
+++ b/src/glx.xml
@@ -92,6 +92,7 @@ The patch that fixed this server bug in X.org CVS is here:
 
 	<!-- Events -->
 	<event name="PbufferClobber" number="0">
+		<pad bytes="1" />
 		<field type="CARD16" name="event_type" />
 		<field type="CARD16" name="draw_type" />
 		<field type="glx:DRAWABLE" name="drawable" />