diff --git a/src/Hpricot.cs b/src/Hpricot.cs
index 9e068e1..83b198e 100644
--- a/src/Hpricot.cs
+++ b/src/Hpricot.cs
@@ -9,12 +9,12 @@ namespace IronRuby.Libraries.Hpricot {
     [RubyModule("Hpricot")]
     public static class Hpricot {
         [RubyMethod("scan", RubyMethodAttributes.PublicSingleton)]
-        public static Object Scan(ConversionStorage<MutableString>/*!*/ toMutableStringStorage, RespondToStorage/*!*/ respondsTo, 
-            RubyContext/*!*/ context, BlockParam/*!*/ block, RubyModule/*!*/ self, Object/*!*/ source) {
+        public static Object Scan(ConversionStorage<MutableString>/*!*/ toMutableStringStorage, RespondToStorage/*!*/ respondsTo,
+            BinaryOpStorage/*!*/ readIOStorage, BlockParam/*!*/ block, RubyModule/*!*/ self, Object/*!*/ source) {
             if (block == null) {
                 throw RubyExceptions.NoBlockGiven();
             }
-            HpricotScanner scanner = new HpricotScanner(respondsTo, toMutableStringStorage, context, block);
+            HpricotScanner scanner = new HpricotScanner(respondsTo, toMutableStringStorage, readIOStorage, block);
             return scanner.Scan(source);
         }
 
diff --git a/src/HpricotScanner.cs b/src/HpricotScanner.cs
index e23219a..0caa920 100644
--- a/src/HpricotScanner.cs
+++ b/src/HpricotScanner.cs
@@ -9,7 +9,7 @@
 using Microsoft.Scripting.Runtime;
 
 namespace IronRuby.Libraries.Hpricot {
-    using RubyIOReadCallSite = CallSite<Func<CallSite, RubyContext, Object, Int32, MutableString>>;
+    using RubyIOReadCallSite = CallSite<Func<CallSite, Object, Object, Object>>;
 
     public class HpricotScanner {
         #region fields
@@ -22,6 +22,7 @@ public class HpricotScanner {
         private BlockParam/*!*/ _blockParam;
         private RespondToStorage/*!*/ _respondToStorage;
         private ConversionStorage<MutableString> _toMutableString;
+        private BinaryOpStorage _readIOStorage;
 
         #endregion
 
@@ -60,11 +61,12 @@ public class HpricotScanner {
 
         #region constructors 
 
-        public HpricotScanner(RespondToStorage/*!*/ respondToStorage, ConversionStorage<MutableString>/*!*/ toMutableString, 
-            RubyContext/*!*/ context, BlockParam/*!*/ block) {
+        public HpricotScanner(RespondToStorage/*!*/ respondToStorage, ConversionStorage<MutableString>/*!*/ toMutableString,
+            BinaryOpStorage/*!*/ readIOStorage, BlockParam block) {
+            _currentContext = respondToStorage.Context;
             _respondToStorage = respondToStorage;
             _toMutableString = toMutableString;
-            _currentContext = context;
+            _readIOStorage = readIOStorage;
             _blockParam = block;
         }
 
@@ -1150,9 +1152,9 @@ public Object Scan(Object/*!*/ source) {
 
             bool sourceRespondsToRead = Protocols.RespondTo(_respondToStorage, source, "read");
 
-            RubyIOReadCallSite readCallSite = null;
+            RubyIOReadCallSite readIOCallSite = null;
             if (sourceRespondsToRead) {
-                readCallSite = RubyIOReadCallSite.Create(RubyCallAction.Make(_currentContext, "read", 3));
+                readIOCallSite = _readIOStorage.GetCallSite("read", 1);
             }
             else if (Protocols.RespondTo(_respondToStorage, source, "to_str")) {
                 source = Protocols.CastToString(_toMutableString, source);
@@ -1184,7 +1186,7 @@ public Object Scan(Object/*!*/ source) {
 
                 char[] chars;
                 if (sourceRespondsToRead) {
-                    chars = BinaryEncoding.Instance.GetChars(readCallSite.Target(readCallSite, _currentContext, source, space).ToByteArray());
+                    chars = BinaryEncoding.Instance.GetChars((readIOCallSite.Target(readIOCallSite, source, space) as MutableString).ToByteArray());
                 }
                 else {
                     MutableString str = source as MutableString;
diff --git a/src/Initializers.Generated.cs b/src/Initializers.Generated.cs
index afbcb9b..8848b6c 100644
--- a/src/Initializers.Generated.cs
+++ b/src/Initializers.Generated.cs
@@ -22,7 +22,7 @@ private static void LoadHpricot_Class(IronRuby.Builtins.RubyModule/*!*/ module)
             );
             
             module.DefineLibraryMethod("scan", 0x21, 
-                new System.Func<IronRuby.Runtime.ConversionStorage<IronRuby.Builtins.MutableString>, IronRuby.Runtime.RespondToStorage, IronRuby.Runtime.RubyContext, IronRuby.Runtime.BlockParam, IronRuby.Builtins.RubyModule, System.Object, System.Object>(IronRuby.Libraries.Hpricot.Hpricot.Scan)
+                new System.Func<IronRuby.Runtime.ConversionStorage<IronRuby.Builtins.MutableString>, IronRuby.Runtime.RespondToStorage, IronRuby.Runtime.BinaryOpStorage, IronRuby.Runtime.BlockParam, IronRuby.Builtins.RubyModule, System.Object, System.Object>(IronRuby.Libraries.Hpricot.Hpricot.Scan)
             );
             
         }