This ones particularly easy because he must be using it for an IRCX Service where the Guest_ is defined in mIRC as a ">". In a typical webchat envrionment ">" is typically replaced so that the nickname reads Guest_Nickname, so that being said, here is the newly modified code below:

Code:
 on @*:JOIN:#: {

 if (*>* !iswm $nick) { mode # +v $v2 }

 }


Hoped this answered your question.