diff --git a/package.json b/package.json
index c8c29d9..977c9de 100755
--- a/package.json
+++ b/package.json
@@ -15,7 +15,7 @@
     }
  , "engine": "node >= 0.4.1"
  , "scripts": {
-   "preinstall": "node-gyp rebuild"
+   "preinstall": "node-gyp clean rebuild"
    , "test": "vows test/unit.js"
  }
  , "main": "./lib/opencv"
diff --git a/src/CascadeClassifierWrap.cc b/src/CascadeClassifierWrap.cc
index e1046b8..6a5c095 100755
--- a/src/CascadeClassifierWrap.cc
+++ b/src/CascadeClassifierWrap.cc
@@ -18,7 +18,7 @@ CascadeClassifierWrap::Init(Handle<Object> target) {
     constructor->SetClassName(String::NewSymbol("CascadeClassifier"));
 
     // Prototype
-    Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
+    //Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
 
     NODE_SET_PROTOTYPE_METHOD(constructor, "detectMultiScale", DetectMultiScale);
 
diff --git a/src/Contours.cc b/src/Contours.cc
index b2f8263..69f80d2 100755
--- a/src/Contours.cc
+++ b/src/Contours.cc
@@ -20,7 +20,7 @@ Contour::Init(Handle<Object> target) {
 	constructor->SetClassName(String::NewSymbol("Contours"));
 
 	// Prototype
-	Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
+	//Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
 
 
 	NODE_SET_PROTOTYPE_METHOD(constructor, "size", Size);
diff --git a/src/Matrix.cc b/src/Matrix.cc
index cfeac3b..0b14461 100755
--- a/src/Matrix.cc
+++ b/src/Matrix.cc
@@ -22,7 +22,7 @@ Matrix::Init(Handle<Object> target) {
 	constructor->SetClassName(String::NewSymbol("Matrix"));
 
 	// Prototype
-	Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
+	//Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
 
 
 	NODE_SET_PROTOTYPE_METHOD(constructor, "row", Row);
diff --git a/src/VideoCaptureWrap.cc b/src/VideoCaptureWrap.cc
index a7a8a85..74bbd9c 100755
--- a/src/VideoCaptureWrap.cc
+++ b/src/VideoCaptureWrap.cc
@@ -28,7 +28,7 @@ VideoCaptureWrap::Init(Handle<Object> target) {
 	constructor->SetClassName(String::NewSymbol("VideoCapture"));
 
 	// Prototype
-	Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
+	//Local<ObjectTemplate> proto = constructor->PrototypeTemplate();
 
 	NODE_SET_PROTOTYPE_METHOD(constructor, "read", Read);