I disabled all the encoding/font related options in Options/IRC/Messages and it still crashed, I did not try different combinations. About the debug.log, is there a detail level to it? Or is this really simply a channel log? Depending on the encoding setting for the log file, the lines that make me crash are
<- :nwa!~defianze@somewhere PRIVMSG #channel :4&#32349;&#33292;&#12539; 7blah in ANSI and
<- :nwa!~defianze@somewhere PRIVMSG nwa :2&#12496;&#12540;6nbn in UTF-8