Issue in checkstyle configuaration in IntelliJ Idea

My objective is to implement Google's Java Style Checkstyle as stated in http://ift.tt/1ET0LMG .

In IntelliJ I have enabled Checkstyle plugin and try to point checkstyle xml ( downloaded from http://ift.tt/1EuY6wf).

I got following exception stated Property 'fileExtensions' in module Checker does not exist though this property is defined in the xml as "property name="fileExtensions" value="java, properties, xml"

Exception details:

org.infernus.idea.checkstyle.exception.CheckStylePluginException: The CheckStyle rules file could not be loaded.

Property 'fileExtensions' in module Checker does not exist, please check the documentation at org.infernus.idea.checkstyle.checker.CheckerFactory.blacklistAndShowMessage(CheckerFactory.java:248) at org.infernus.idea.checkstyle.checker.CheckerFactory.createChecker(CheckerFactory.java:202)