Android : How To get LastActivity from ejbbered server using smack library?

I am sending below request for getting the LastActivity(Last seen status) of the below user from ejabbered server using smack library in android.

try {
    Packet pk = new Packet() {

        @Override
        public String toXML() {
            // TODO Auto-generated method stub
            return "<iq from='" + Utils.createJabberUserIdByUserId(me.getUserId()) + "'" + " id='last1' "
                    + " to='" + Utils.createJabberUserIdByUserId(friendId) + "' " + " type='get'> "
                    + "<query xmlns='jabber:iq:last'/>" + "</iq>";
        }
    };
    ConnectionManager.getInstance().getXmppConnection().sendPacket(pk);
} catch (Exception e) {
    // TODO: handle exception
}

Result I got from the server is:

 <iq from="272@jabber.com">
     id="last1"
     to="274@jabber.com/64faf3314bee33c4" 
     type="result"
 </iq>

But the result should be like this:

<iq from='272@jabber.com' 
    id='last1'
    to='274@jabber.com/64faf3314bee33c4'
    type='result'>
  <query xmlns='jabber:iq:last' seconds='903'/>
</iq>

What am I doing wrong? please help.