diff --git a/lib/oauth.js b/lib/oauth.js
index 671462f..66a21b8 100644
--- a/lib/oauth.js
+++ b/lib/oauth.js
@@ -70,6 +70,20 @@ exports.OAuth.prototype._normalizeUrl= function(url) {
   return parsedUrl.protocol + "//" + parsedUrl.hostname + port + parsedUrl.pathname;
 }
 
+// build the OAuth request authorization header
+exports.OAuth.prototype._buildAuthorizationHeaders= function(orderedParameters) {
+  var authHeader="OAuth "; 
+  for( var i= 0 ; i < orderedParameters.length; i++) { 
+     // Whilst the all the parameters should be included within the signature, only the oauth_ arguments
+     // should appear within the authorization header.
+     if( orderedParameters[i][0].match('^oauth_') == "oauth_") {
+      authHeader+= this._encodeData(orderedParameters[i][0])+"=\""+ this._encodeData(orderedParameters[i][1])+"\",";
+     }
+  }
+  authHeader= authHeader.substring(0, authHeader.length-1);
+  return authHeader;
+}
+
 // Takes a literal in, then returns a sorted array
 exports.OAuth.prototype._sortRequestParams= function(argumentsHash) {
   var argument_pairs= [];
@@ -196,19 +210,7 @@ exports.OAuth.prototype._performSecureRequest= function( oauth_token, oauth_toke
   }
 
   var headers= {};
-
-  // build request authorization header
-  var authHeader="OAuth "; 
-  for( var i= 0 ; i < orderedParameters.length; i++) { 
-     // Whilst the all the parameters should be included within the signature, only the oauth_ arguments
-     // should appear within the authorization header.
-     if( orderedParameters[i][0].match('^oauth_') == "oauth_") {
-      authHeader+= this._encodeData(orderedParameters[i][0])+"=\""+ this._encodeData(orderedParameters[i][1])+"\",";
-     }
-  }
-  authHeader= authHeader.substring(0, authHeader.length-1);
-
-  headers["Authorization"]= authHeader;
+  headers["Authorization"]= this._buildAuthorizationHeaders(orderedParameters);
   headers["Host"] = parsedUrl.host
 
   for( var key in this._headers ) {