diff --git a/Data/GPS/Trail.hs b/Data/GPS/Trail.hs
--- a/Data/GPS/Trail.hs
+++ b/Data/GPS/Trail.hs
@@ -402,7 +402,7 @@
 	in case first of
 		Nothing -> []
 		Just f  ->
-	    	     let sorted = sortBy (comparing (eastZeroHeading f)) (filter (/= f) xs)
+	    	     let sorted = L.sortBy (comparing (eastZeroHeading f)) (filter (/= f) xs)
 		     in case sorted of
 			(a:b:cs) -> grahamScan (b:a:f:[]) cs
 			cs       -> f : cs
diff --git a/gps.cabal b/gps.cabal
--- a/gps.cabal
+++ b/gps.cabal
@@ -1,5 +1,5 @@
 name:		gps
-version:	0.8.3
+version:	0.8.4
 license:	BSD3
 license-file:	LICENSE
 author:		Thomas DuBuisson <thomas.dubuisson@gmail.com>