diff --git a/lib/geocoder.rb b/lib/geocoder.rb
index a8c37ae9615f4f98f26b7ac95746f733d2b7c7e0..a68acff510cf5d4ac4e2c8fba4a126731be924f5 100644
--- a/lib/geocoder.rb
+++ b/lib/geocoder.rb
@@ -2,7 +2,6 @@
 # Add geocoding functionality (via Google) to any object.
 #
 module Geocoder
-  include Math
   
   ##
   # Implementation of 'included' hook method.
@@ -208,9 +207,9 @@ module Geocoder
     dlat = (lat1 - lat2).abs
     dlon = (lon1 - lon2).abs
     
-    a = (sin(dlat / 2))**2 + cos(lat1) *
-        (sin(dlon / 2))**2 * cos(lat2)  
-    c = 2 * atan2( sqrt(a), sqrt(1-a))  
+    a = (Math.sin(dlat / 2))**2 + Math.cos(lat1) *
+        (Math.sin(dlon / 2))**2 * Math.cos(lat2)  
+    c = 2 * Math.atan2( Math.sqrt(a), Math.sqrt(1-a))  
     c * units[options[:units]]
   end
   
@@ -246,7 +245,7 @@ module Geocoder
   # Convert degrees to radians.
   #
   def self.to_radians(degrees)
-    degrees * (PI / 180)
+    degrees * (Math::PI / 180)
   end
   
   ##