diff --git a/.hgtags b/.hgtags
--- a/.hgtags
+++ b/.hgtags
@@ -3,3 +3,4 @@ 73524cc41d6c6f4a664b39a74ae202be21b58eaf
 1332b87e543fd947b57d45ccf62e9a0886e09cb5 v0.3
 92b7092ddffa87776c7886dc071113416f772860 v0.4
 11a1ee6b27d1cd655193cfdc032aab76ad7a743c v0.5
+878ad8de497561098a63a0d21d36b103cea0719c v0.5.1