diff --git a/pipes-concurrency.cabal b/pipes-concurrency.cabal
--- a/pipes-concurrency.cabal
+++ b/pipes-concurrency.cabal
@@ -1,5 +1,5 @@
 Name: pipes-concurrency
-Version: 2.0.4
+Version: 2.0.5
 Cabal-Version: >=1.8.0.2
 Build-Type: Simple
 License: BSD3
@@ -48,4 +48,4 @@
         pipes             >= 4.0.0 && < 4.2,
         pipes-concurrency >= 2.0.0 && < 2.1,
         stm               >= 2.4.3 && < 2.5,
-        async             >= 2.0   && < 2.1
+        async             >= 2.0   && < 2.2