diff -r caf81db532ed -r 6aba07ea908b gameServer/CoreTypes.hs
--- a/gameServer/CoreTypes.hs	Tue Jun 02 19:53:30 2015 +0100
+++ b/gameServer/CoreTypes.hs	Wed Jun 03 23:24:56 2015 +0300
@@ -38,7 +38,7 @@
 instance NFData B.ByteString
 #endif
 
-instance NFData (Chan a) where rnf a  = ()
+instance NFData (Chan a) where rnf a  = a `seq` ()
 
 instance NFData Action where
     rnf (AnswerClients chans msg) = chans `deepseq` msg `deepseq` ()