iqRouter not sending ping

Hi, im trying to make a plugin that will send an IQ ping to the connected clients. However, when I execute it, client receive nothing. Any idea why ? below is my code and thanks in advanced!

public void sendMessage(String from, String to) {

final Message message = new Message();

final XMPPServer xmppServer = XMPPServer.getInstance();

JID toAddress = new JID(to+"@"+serverName);

JID fromAddress = new JID(from+"@"+serverName);

//message.setTo(toAddress);

//message.setFrom(fromAddress);

//message.setSubject(getSubject());

//message.setBody(getMessage());

// For testing purpose

IQRouter iqRouter = XMPPServer.getInstance().getIQRouter();

IQ iq = new IQ();

iq.setTo(toAddress);

iq.setFrom(fromAddress);

iq.setType(IQ.Type.get);

iq.setChildElement(“ping”,“urn:xmpp:ping”);

iqRouter.route(iq);

//router.route(message);

}