include utf-8 specification in http header and replace "(" and ")" with their url encoded versions: %28 and %29 before signing the string.

Author: crcastle

lib/aws.js

@@ -42,7 +42,7 @@ var genericAWSClient = function(obj) {
     var body = qs.stringify(query);
     var headers = {
       "Host": obj.host,
-      "Content-Type": "application/x-www-form-urlencoded",
+      "Content-Type": "application/x-www-form-urlencoded; charset=utf-8",
       "Content-Length": body.length
     };
 
@@ -99,6 +99,8 @@ var genericAWSClient = function(obj) {
     // Amazon signature algorithm seems to require this
     stringToSign = stringToSign.replace(/'/g,"%27");
     stringToSign = stringToSign.replace(/\*/g,"%2A");
+    stringToSign = stringToSign.replace(/\(/g,"%28");
+    stringToSign = stringToSign.replace(/\)/g,"%29");
 
     return hmacSha256(obj.secretAccessKey, stringToSign);
   }