diff --git a/test/Makefile.am b/test/Makefile.am
index df69d0fda..d92014f6a 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -252,7 +252,8 @@ trap-clip-rgb24-ref.png					\
 unantialiased-shapes-ref.png				\
 unantialiased-shapes-ps-argb32-ref.png			\
 unbounded-operator-ref.png				\
-unbounded-operator-rgb24-ref.png
+unbounded-operator-rgb24-ref.png			\
+zero-alpha-ref.png
 
 # Any test for which the code committed to CVS is expected to fail
 # should be listed here.