Index: image.module
===================================================================
--- image.module	(revision 6233)
+++ image.module	(working copy)
@@ -973,10 +973,12 @@
  */
 function image_style_url($style_name, $path) {
   $uri = image_style_path($style_name, $path);
+  //Normalize the path. 
+  $path = image_style_path_normalize($path);
   // The token query is added even if the 'image_allow_insecure_derivatives'
   // variable is TRUE, so that the emitted links remain valid if it is changed
   // back to the default FALSE.
@@ -1040,6 +1042,23 @@
 }
 
 /**
+ * Add schema to the $uri parameter if no schema in the path. 
+ * @param string 
+ *  $path
+ * @return string 
+ *  $uri
+ */
+function image_style_path_normalize($uri) {
+  $scheme = file_uri_scheme($uri);
+  if (!$scheme) {
+    $scheme = file_default_scheme();
+    $uri = $scheme . '://' . $uri;
+  }
+  
+  return $uri;
+}
+
+/**
  * Save a default image style to the database.
  *
  * @param style