diff --git a/awsapi/src/com/cloud/bridge/service/EC2RestServlet.java b/awsapi/src/com/cloud/bridge/service/EC2RestServlet.java
index 5d151bac7e4..b5296a4699e 100644
--- a/awsapi/src/com/cloud/bridge/service/EC2RestServlet.java
+++ b/awsapi/src/com/cloud/bridge/service/EC2RestServlet.java
@@ -1899,10 +1899,14 @@ public class EC2RestServlet extends HttpServlet {
                     String paramName = (String) params.nextElement();
                     // exclude the signature string obviously. ;)
                     if (paramName.equalsIgnoreCase("Signature")) continue;
+                    // URLEncoder performs application/x-www-form-urlencoded-type encoding and not Percent encoding
+                    // according to RFC 3986 as required by Amazon, we need to Percent-encode (URL Encode)
+                    String encodedValue = URLEncoder.encode(request.getParameter(paramName), "UTF-8")
+                            .replace("+", "%20").replace("*", "%2A");
                     if (queryString == null) 
-                        queryString = paramName + "=" + URLEncoder.encode(request.getParameter(paramName), "UTF-8"); 
+                        queryString = paramName + "=" + encodedValue;
                     else 
-                        queryString = queryString + "&" + paramName + "=" + URLEncoder.encode(request.getParameter(paramName), "UTF-8"); 
+                        queryString = queryString + "&" + paramName + "=" + encodedValue;
                 }
             }
         }