diff --git a/Makefile b/Makefile
index 16e8bac..f36c5c3 100644
--- a/Makefile
+++ b/Makefile
@@ -30,6 +30,7 @@ UPGRADABLE = \
   0.4.0 \
   0.4.1 \
   0.5.0 \
+  0.5.1 \
   $(EXTVERSION)dev \
   $(EXTVERSION)next \
   $(END)