How to call soapheader function in soapclient php5?

[sganeshsvk]

How to call soapheader function in soapclient php5?

I want to call the <soap header> xml in soapclient php.
so i want to use soapheader function in soapclient php5.
please code for example how to declare soapheader in soapclient.

<?php

function OrderImport()
	{
		$this->_soapclient = new SEG_SoapClient('OrderImportProxy');
		$this->_soapclient->__soapCall("echoVoid", new SoapHeader('http://www.openuri.org/2002/04/soap/conversation/','StartHeader','conversationID','callbackLocation'));

?>