} else if ( response.getStatusCode() == Response.PROXY_AUTHENTICATION_REQUIRED) {
AuthenticationHelper authenticationHelper =
((SipStackExt) protocolObjects.sipStack).getAuthenticationHelper(new AccountManagerImpl(),
protocolObjects.headerFactory);
tid = authenticationHelper.handleChallenge(response, (ClientTransaction) tid, provider, 5);
Thread.sleep(100);
if ( dialog.getState() == DialogState.CONFIRMED) {
dialog.sendRequest((ClientTransaction) tid);
} else {
((ClientTransaction)tid).sendRequest();