title: Strophe gets invalid SID
body: <p>I'm building a web based client with strophe and jquery and I'm using openfire as server. 
  Almost everything its working, I can get the roster list, send and receive messages, but when I'm trying to change my presence from avaliable to xa or dnd or any other else the server stops answering and I start to get 404 errors on my POSTs and invalid SID messages like this: "NetworkError: 404 Invalid SID. - <a href="http://myurl.com/" rel="noreferrer">http://myurl.com/</a>".</p>
  
  <p>I've been through other topics around and it seems to be a problem with my avaliable credentials, but I don't have any clear evidence of what's wrong.</p>
  
  <p>thanks in advance for any help.</p>