from and to mismatch on ping

Apr 09 20:19:35 ciboule biboumi[23362]: src/irc/irc_client.cpp:165:        IRC SENDING: (irc.t411.io) IrcMessage[PRIVMSG]{#t411}{.ping}                                                        
Apr 09 20:19:35 ciboule biboumi[23362]: louloulibs/xmpp/xmpp_component.cpp:75:        XMPP SENDING: .ping                                                                                                                                                            
Apr 09 20:19:36 ciboule biboumi[23362]: [135B blob data]                                                                                                                                       
Apr 09 20:19:36 ciboule biboumi[23362]: louloulibs/xmpp/xmpp_component.cpp:75:        XMPP SENDING:                                                                                                                                                         
Apr 09 20:19:36 ciboule biboumi[23362]: louloulibs/xmpp/xmpp_component.cpp:174:        XMPP RECEIVING:                                                                                                                                                    
Apr 09 20:19:36 ciboule biboumi[23362]: src/xmpp/biboumi_component.cpp:538:        Received a corresponding ping result, but the 'to' from the response mismatches the 'from' of the request   

The mismatch is apparently due to case change, the

from='Gaya!irc.t411.io@irc.poez.io' 

is invalid.

(from redmine: created on 2015-04-09, closed on 2015-05-11)