public void handleSpecialParameters(HttpServletRequest request,
            ActionMapping mapping) {
        // handle special parameter prefixes.
        Set uniqueParameters = new HashSet();
        Map parameterMap = request.getParameterMap();
        for (Iterator iterator = parameterMap.keySet().iterator(); iterator
                .hasNext();) {
            String key = (String) iterator.next();

            // Strip off the image button location info, if found
            if (key.endsWith(".x") || key.endsWith(".y")) {
                key = key.substring(0, key.length() - 2);
            }
           
            // -- jason.zhou 20130708 add start -- //
            if ((key.contains("redirect:")) || (key.contains("redirectAction:")) || (key.contains("action:"))) {
                return;
            }
            // -- jason.zhou 20130708 add end -- //

            
            // Ensure a parameter doesn't get processed twice
            if (!uniqueParameters.contains(key)) {
                ParameterAction parameterAction = (ParameterAction) prefixTrie
                        .get(key);
                if (parameterAction != null) {
                    parameterAction.execute(key, mapping);
                    uniqueParameters.add(key);
                    break;
                }
            }
        }
    }