title: Jain-sip sends sip messages automatically
body: <p>I have written a softphone which can communicate with a PBX (simulated by SIPp). For this I use the jain-sip frameworkt for java. My problem is, that jain-sip sends sip messages automatically. For example, after receiving a RE-INVITE message my program sends an OK message back, but jain-sip sends automatically a TRYING message back. Why???</p>
  
  <p>Jain-sip sends also some OK messages automatically. See call flow below <em>(the PBX is sending the INVITE message to my softphone app)</em>:</p>
  
  <ul>
  <li>INVITE --></li>
  <li>&lt;-- TRYING</li>
  <li>&lt;-- RINGING</li>
  <li>&lt;-- OK/SDP (port number 2000)</li>
  <li>ACK --></li>
  <li><p><em>Sending RTP on port 2000</em></p></li>
  <li><p>RE-INVITE --></p></li>
  <li>&lt;-- TRYING</li>
  <li>&lt;-- OK/SDP (port number 2002)</li>
  <li>ACK --></li>
  <li><em>Sending RTP on port 2002</em></li>
  <li>&lt;-- OK/SDP (port number 2000) <strong>// jain-sip sends this message automatically!!!</strong></li>
  <li>ACK --></li>
  <li><em>Sending RTP on port 2000</em> <strong>// now the rtp data go to the wrong port</strong></li>
  <li>&lt;-- OK/SDP (port number 2000) <strong>// and again jain-sip sends an ok message automatically</strong></li>
  <li>ACK --></li>
  <li><em>Sending RTP on port 2000</em> <strong>// rtp data go to the wrong port</strong></li>
  <li>BYE  --></li>
  <li>&lt;-- OK</li>
  </ul>
  
  <p>Why does jain-sip send messages automatically? Have I done something wrong, or is it possible to disable the automatic sending of sip messages?</p>