diff --git a/Control/Event.hs b/Control/Event.hs
--- a/Control/Event.hs
+++ b/Control/Event.hs
@@ -3,16 +3,16 @@
 -- requiring later IO actions.  For a simpler system that uses relative times
 -- see Control.Event.Relative
 module Control.Event (
-	 EventId
-	,EventSystem
-	,noEvent
-	,initEventSystem
-	,addEvent
-	,addEventSTM
-	,cancelEvent
-	,cancelEventSTM
-	,evtSystemSize
-	) where
+         EventId
+        ,EventSystem
+        ,noEvent
+        ,initEventSystem
+        ,addEvent
+        ,addEventSTM
+        ,cancelEvent
+        ,cancelEventSTM
+        ,evtSystemSize
+        ) where
 
 import Prelude hiding (lookup, catch)
 import Control.Concurrent (forkIO, myThreadId, ThreadId, threadDelay)
@@ -75,10 +75,10 @@
 -- earlier, alarm time.
 expireEvents :: EventSystem -> IO ()
 expireEvents es = do
-	block (do
-		tid <- myThreadId
-		forever $ catch (unblock (setTID (Just tid) es >> expireEvents' es))
-				(\TimerReset -> return ()) )
+        block (do
+                tid <- myThreadId
+                forever $ catch (unblock (setTID (Just tid) es >> expireEvents' es))
+                                (\TimerReset -> return ()) )
   where
   setTID i es = atomically (writeTVar (esThread es) i)
 
@@ -113,17 +113,17 @@
                     writeTVar (esAlarm evtSys) newAlarm
                     writeTVar (esEvents evtSys) newMap
                     exps <- readTVar (esExpired evtSys)
-		    writeTVar (esExpired evtSys) (exp:exps) )
+                    writeTVar (esExpired evtSys) (exp:exps) )
   where
   getEarlierKeys :: UTCTime -> Map UTCTime EventSet -> ([EventSet], Map UTCTime EventSet)
   getEarlierKeys clk m =
       case deleteFindMinM m of
           Just ((k,es), m') ->
-	      if k < clk
-	          then let (exp, lastMap) = getEarlierKeys clk m'
-	               in (es:exp, lastMap)
-		  else ([], m)
-	  Nothing -> ([], m)
+              if k < clk
+                  then let (exp, lastMap) = getEarlierKeys clk m'
+                       in (es:exp, lastMap)
+                  else ([], m)
+          Nothing -> ([], m)
 
   getAlarm m | size m == 0 = never
              | otherwise   = fst $ findMin m
@@ -136,9 +136,9 @@
 monitorExpiredQueue exp = do
     exp <- atomically (do
                e <- readTVar exp
-	       case e of
-	           (a:as) -> writeTVar exp [] >> return e
-		   _      -> retry )
+               case e of
+                   (a:as) -> writeTVar exp [] >> return e
+                   _      -> retry )
     mapM_ (mapM_ runEvents) exp
 
 -- |Runs all provided events (which must have expired)
@@ -159,7 +159,7 @@
         num = case old of
                  Nothing    -> 0
                  Just (n,_) -> n
-	eid = EvtId clk num 
+        eid = EvtId clk num 
     writeTVar (esEvents sys) newMap
     alm <- readTVar (esAlarm sys)
     when (clk < alm || alm == never)
@@ -183,10 +183,10 @@
         prev :: Maybe EventSet
         (prev,newMap) = insertLookupWithKey (\_ _ (cnt, old) -> (cnt,delete num old)) clk undefined evts
         ret = case prev of
-		Nothing -> False -- error "Canceling an event that never existed."
-		Just (_,p)  -> case lookup clk newMap of
-					Nothing -> False
-					Just (_,m)  -> (size p /= size m)
+                Nothing -> False -- error "Canceling an event that never existed."
+                Just (_,p)  -> case lookup clk newMap of
+                                        Nothing -> False
+                                        Just (_,m)  -> (size p /= size m)
     when (eid /= noEvent) (writeTVar (esEvents sys) newMap)
     return (eid == noEvent || ret)
 
@@ -202,12 +202,12 @@
 trackAlarm sys = do
     tid <- atomically (do
                newAlm <- readTVar (esNewAlarm sys)
-	       if newAlm then writeTVar (esNewAlarm sys) False else retry
+               if newAlm then writeTVar (esNewAlarm sys) False else retry
 
                tid <- readTVar (esThread sys)
-	       i <- case tid of
-	                Just i  -> return i
-			Nothing -> retry
+               i <- case tid of
+                        Just i  -> return i
+                        Nothing -> retry
                return i )
     throwTo tid TimerReset
 
diff --git a/control-event.cabal b/control-event.cabal
--- a/control-event.cabal
+++ b/control-event.cabal
@@ -1,5 +1,5 @@
 name:                control-event
-version:             1.2.1.0
+version:             1.2.1.1
 synopsis:            Event scheduling system.
 description:         Allows scheduling and canceling of IO actions to be
                      executed at a specified future time.
@@ -16,8 +16,8 @@
 
 Library
   build-Depends:       base >= 4.0 && < 5,
-                       time >= 1.1 && < 1.3,
-                       containers >= 0.1 && < 0.5,
-                       stm >= 2.1 && < 2.3
+                       time >= 1.1,
+                       containers >= 0.1,
+                       stm >= 2.1
   extensions:          DeriveDataTypeable
   exposed-modules:     Control.Event, Control.Event.Timeout, Control.Event.Relative