diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,7 @@
+### 1.2.1
+
+- Bugfix: put *unsigned* integers in event channels (important for *eventfd*).
+
 ### 1.2.0
 
 - Added exporter *ngxExportServiceHook* for service hooks and exception
diff --git a/NgxExport.hs b/NgxExport.hs
--- a/NgxExport.hs
+++ b/NgxExport.hs
@@ -362,11 +362,6 @@
         poke (castPtr p) n
         poke (plusPtr p $ alignment x) s
 
-data ServiceHookInterrupt = ServiceHookInterrupt
-instance Exception ServiceHookInterrupt
-instance Show ServiceHookInterrupt where
-    show = const "Service was interrupted by a service hook"
-
 safeMallocBytes :: Int -> IO (Ptr a)
 safeMallocBytes =
     flip catchIOError (const $ return nullPtr) . mallocBytes
@@ -540,10 +535,10 @@
 ioyYWithFree = ioyYCommon B.unsafePackMallocCStringLen
 
 asyncIOFlag1b :: B.ByteString
-asyncIOFlag1b = L.toStrict $ runPut $ putInt8 1
+asyncIOFlag1b = L.toStrict $ runPut $ putWord8 1
 
 asyncIOFlag8b :: B.ByteString
-asyncIOFlag8b = L.toStrict $ runPut $ putInt64host 1
+asyncIOFlag8b = L.toStrict $ runPut $ putWord64host 1
 
 asyncIOCommon :: IO (L.ByteString, Bool) ->
     CInt -> Bool -> Ptr (Ptr NgxStrType) -> Ptr CInt ->
@@ -744,6 +739,12 @@
     StablePtr (Async ()) -> IO ()
 ngxExportTerminateTask = deRefStablePtr >=>
     cancel
+
+data ServiceHookInterrupt = ServiceHookInterrupt
+
+instance Exception ServiceHookInterrupt
+instance Show ServiceHookInterrupt where
+    show = const "Service was interrupted by a service hook"
 
 foreign export ccall ngxExportServiceHookInterrupt ::
     StablePtr (Async ()) -> IO ()
diff --git a/ngx-export.cabal b/ngx-export.cabal
--- a/ngx-export.cabal
+++ b/ngx-export.cabal
@@ -1,5 +1,5 @@
 name:                       ngx-export
-version:                    1.2.0
+version:                    1.2.1
 synopsis:                   Helper module for Nginx haskell module
 description:                Helper module for
         <http://github.com/lyokha/nginx-haskell-module Nginx haskell module>