diff --git a/haste-compiler.cabal b/haste-compiler.cabal
--- a/haste-compiler.cabal
+++ b/haste-compiler.cabal
@@ -1,5 +1,5 @@
 Name:           haste-compiler
-Version:        0.4
+Version:        0.4.1
 License:        BSD3
 License-File:   LICENSE
 Synopsis:       Haskell To ECMAScript compiler
diff --git a/lib/rts.js b/lib/rts.js
--- a/lib/rts.js
+++ b/lib/rts.js
@@ -88,14 +88,15 @@
     return f;
 }
 
-// Export Haste, A and E. Haste because we need to preserve exports, A and E
-// because they're handy for Haste.Foreign.
+// Export Haste, A, B and E. Haste because we need to preserve exports, A, B
+// and E because they're handy for Haste.Foreign.
 if(!window) {
     var window = {};
 }
 window['Haste'] = Haste;
 window['A'] = A;
 window['E'] = E;
+window['B'] = B;
 
 
 /* Throw an error.
@@ -199,7 +200,7 @@
 function unFoldrCStr(str, f, z) {
     var acc = z;
     for(var i = str.length-1; i >= 0; --i) {
-        acc = A(f, [[0, str.charCodeAt(i)], acc]);
+        acc = B(A(f, [[0, str.charCodeAt(i)], acc]));
     }
     return acc;
 }
@@ -246,7 +247,7 @@
 
 // atomicModifyMutVar
 function mMV(mv, f) {
-    var x = A(f, [mv.x]);
+    var x = B(A(f, [mv.x]));
     mv.x = x[1];
     return x[2];
 }
@@ -289,9 +290,9 @@
 
 function jsCatch(act, handler) {
     try {
-        return A(act,[0]);
+        return B(A(act,[0]));
     } catch(e) {
-        return A(handler,[e, 0]);
+        return B(A(handler,[e, 0]));
     }
 }
 
diff --git a/lib/stdlib.js b/lib/stdlib.js
--- a/lib/stdlib.js
+++ b/lib/stdlib.js
@@ -63,7 +63,7 @@
     if(evt == 'change' && elem.type.toLowerCase() == 'text') {
         setCB(elem, 'keyup', function(k) {
             if(k == '\n'.charCodeAt(0)) {
-                A(cb,[[0,k.keyCode],0]);
+                B(A(cb,[[0,k.keyCode],0]));
             }
         });
     }
@@ -78,7 +78,7 @@
             var mpos = jsGetMouseCoords(x);
             var mx = [0,mpos[0]];
             var my = [0,mpos[1]];
-            A(cb,[[0,x.button],[0,mx,my],0]);
+            B(A(cb,[[0,x.button],[0,mx,my],0]));
         };
         break;
     case 'mousemove':
@@ -87,16 +87,16 @@
             var mpos = jsGetMouseCoords(x);
             var mx = [0,mpos[0]];
             var my = [0,mpos[1]];
-            A(cb,[[0,mx,my],0]);
+            B(A(cb,[[0,mx,my],0]));
         };
         break;
     case 'keypress':
     case 'keyup':
     case 'keydown':
-        fun = function(x) {A(cb,[[0,x.keyCode],0]);};
+        fun = function(x) {B(A(cb,[[0,x.keyCode],0]));};
         break;        
     default:
-        fun = function() {A(cb,[0]);};
+        fun = function() {B(A(cb,[0]));};
         break;
     }
     return setCB(elem, evt, fun);
@@ -114,7 +114,7 @@
 }
 
 function jsSetTimeout(msecs, cb) {
-    window.setTimeout(function() {A(cb,[0]);}, msecs);
+    window.setTimeout(function() {B(A(cb,[0]));}, msecs);
 }
 
 function jsGet(elem, prop) {
@@ -337,9 +337,9 @@
     xhr.onreadystatechange = function() {
         if(xhr.readyState == 4) {
             if(xhr.status == 200) {
-                A(cb,[[1,[0,xhr.responseText]],0]);
+                B(A(cb,[[1,[0,xhr.responseText]],0]));
             } else {
-                A(cb,[[0],0]); // Nothing
+                B(A(cb,[[0],0])); // Nothing
             }
         }
     }
diff --git a/libraries/haste-lib/src/Haste/Binary.hs b/libraries/haste-lib/src/Haste/Binary.hs
--- a/libraries/haste-lib/src/Haste/Binary.hs
+++ b/libraries/haste-lib/src/Haste/Binary.hs
@@ -46,7 +46,7 @@
       
       convertBlob :: Blob -> Opaque (Unpacked -> IO ()) -> IO ()
       convertBlob = ffi
-        "(function(b,cb){var r=new FileReader();r.onload=function(){A(cb,[new DataView(r.result),0]);};r.readAsArrayBuffer(b);})"
+        "(function(b,cb){var r=new FileReader();r.onload=function(){B(A(cb,[new DataView(r.result),0]));};r.readAsArrayBuffer(b);})"
 
   getBlobText' b = do
       res <- newEmptyMVar
@@ -55,7 +55,7 @@
     where
       convertBlob :: Blob -> Opaque (JSString -> IO ()) -> IO ()
       convertBlob = ffi
-        "(function(b,cb){var r=new FileReader();r.onload=function(){A(cb,[[0,r.result],0]);};r.readAsText(b);})"
+        "(function(b,cb){var r=new FileReader();r.onload=function(){B(A(cb,[[0,r.result],0]));};r.readAsText(b);})"
 
 -- | Somewhat efficient serialization/deserialization to/from binary Blobs.
 --   The layout of the binaries produced/read by get/put and encode/decode may
diff --git a/libraries/haste-lib/src/Haste/Concurrent.hs b/libraries/haste-lib/src/Haste/Concurrent.hs
--- a/libraries/haste-lib/src/Haste/Concurrent.hs
+++ b/libraries/haste-lib/src/Haste/Concurrent.hs
@@ -2,12 +2,12 @@
              EmptyDataDecls #-}
 -- | Concurrency for Haste. Includes MVars, forking, Ajax and more.
 module Haste.Concurrent (
-    module Monad, module Ajax,
+    module Haste.Concurrent.Monad, module Ajax,
     Recv, Send, Inbox, Outbox, MBox,
     receive, spawn, statefully, (!), (<!),
     wait
   ) where
-import Haste.Concurrent.Monad as Monad
+import Haste.Concurrent.Monad
 import Haste.Concurrent.Ajax as Ajax hiding ((!))
 import Haste.Callback
 
diff --git a/libraries/haste-lib/src/Haste/Foreign.hs b/libraries/haste-lib/src/Haste/Foreign.hs
--- a/libraries/haste-lib/src/Haste/Foreign.hs
+++ b/libraries/haste-lib/src/Haste/Foreign.hs
@@ -271,7 +271,7 @@
              "  return (function() {" ++
              "      var args=Array.prototype.slice.call(arguments,0);"++
              "      args.push(0);" ++
-             "      return E(A(f, args));" ++
+             "      return E(B(A(f, args)));" ++
              "    });" ++
              "})")
 
diff --git a/libraries/haste-lib/src/Haste/Hash.hs b/libraries/haste-lib/src/Haste/Hash.hs
--- a/libraries/haste-lib/src/Haste/Hash.hs
+++ b/libraries/haste-lib/src/Haste/Hash.hs
@@ -44,7 +44,7 @@
             \var oldhash = window.__old_hash;\
             \var newhash = window.location.hash.split('#')[1] || '';\
             \window.__old_hash = newhash;\
-            \A(cb, [[0,oldhash],[0,newhash],0]);\
+            \B(A(cb, [[0,oldhash],[0,newhash],0]));\
           \};\
        \})"
 
diff --git a/libraries/haste-lib/src/Haste/WebSockets.hs b/libraries/haste-lib/src/Haste/WebSockets.hs
--- a/libraries/haste-lib/src/Haste/WebSockets.hs
+++ b/libraries/haste-lib/src/Haste/WebSockets.hs
@@ -84,9 +84,9 @@
     -> IO ()
 new = ffi "(function(url, cb, f, err) {\
              \var ws = new WebSocket(url);\
-             \ws.onmessage = function(e) {A(cb,[ws, [0,e.data],0]);};\
-             \ws.onopen = function(e) {A(f,[ws,0]);};\
-             \ws.onerror = function(e) {A(err,[0]);};\
+             \ws.onmessage = function(e) {B(A(cb,[ws, [0,e.data],0]));};\
+             \ws.onopen = function(e) {B(A(f,[ws,0]));};\
+             \ws.onerror = function(e) {B(A(err,[0]));};\
              \return ws;\
            \})" 
 
@@ -98,9 +98,9 @@
 newBin = ffi "(function(url, cb, f, err) {\
                 \var ws = new WebSocket(url);\
                 \ws.binaryType = 'blob';\
-                \ws.onmessage = function(e) {A(cb,[ws,e.data,0]);};\
-                \ws.onopen = function(e) {A(f,[ws,0]);};\
-                \ws.onerror = function(e) {A(err,[0]);};\
+                \ws.onmessage = function(e) {B(A(cb,[ws,e.data,0]));};\
+                \ws.onopen = function(e) {B(A(f,[ws,0]));};\
+                \ws.onerror = function(e) {B(A(err,[0]));};\
                 \return ws;\
               \})" 
 
diff --git a/src/Haste/Version.hs b/src/Haste/Version.hs
--- a/src/Haste/Version.hs
+++ b/src/Haste/Version.hs
@@ -9,7 +9,7 @@
 import Haste.Environment (hasteSysDir, ghcBinary)
 
 hasteVersion :: Version
-hasteVersion = Version [0, 4] []
+hasteVersion = Version [0, 4, 1] []
 
 ghcVersion :: String
 ghcVersion = unsafePerformIO $ do