Soap UI extension not working

It's not working even for me, I am using SOAPUI 4.6.4 free version. Need help on this ASAP.

performance-assertion-listeners.xml
<?xml version="1.0" encoding="UTF-8"?>
<tns:soapui-listeners xmlns:tns="http://eviware.com/soapui/config">

<tns:listener id="WagSvcPerfAssertionListener" listenerClass="soapui.WagSvcPerfAssertionListener" listenerInterface="com.eviware.soapui.model.testsuite.TestRunListener" />

</tns:soapui-listeners>


Java class

package soapui;

import com.eviware.soapui.SoapUI;
import com.eviware.soapui.model.support.TestRunListenerAdapter;
import com.eviware.soapui.model.testsuite.TestCaseRunContext;
import com.eviware.soapui.model.testsuite.TestCaseRunner;

public class WagSvcPerfAssertionListener extends TestRunListenerAdapter
{
private long startTime;

public void beforeRun( TestCaseRunner testRunner, TestCaseRunContext runContext )
{
startTime = System.nanoTime();
}

public void afterRun( TestCaseRunner testRunner, TestCaseRunContext runContext )
{
long endTime = System.nanoTime();
SoapUI.log( "TestCase [" + testRunner.getTestCase().getName() + "] took " + (endTime-startTime) +
" nanoseconds." );
}
}