XMPPMessage Thread APIs
XMPPStream Did Fail to Send APIs

- (void)xmppStream:(XMPPStream *)sender didFailToSendIQ:(XMPPIQ *)iq error:(NSError *)error;

- (void)xmppStream:(XMPPStream *)sender didFailToSendMessage:(XMPPMessage *)message error:(NSError *)error;

- (void)xmppStream:(XMPPStream *)sender didFailToSendPresence:(XMPPPresence *)presence error:(NSError *)error;
XEP-0106: JID Escaping

Fixes #222