I don't know if TCS still have contract but this company is http://www.broadvision.com/en/customers_aeroxchange.php part of it. When I tried to get PNR status, I once got this error,

javax.servlet.jsp.JspException: No bean found for attribute key historyDetails and rest of the stack trace. From stacktrace, they are using struts and broadvision's some customized servlet container, most likely tomcat.