Why do you need
Code:
if (StrEqual(sCommand, "say"))
on Command_hidetag callback and OnClientSayCommand forward ?
that is useless, just remove it because :
_ OnClientSayCommand is triggered when a player wrote in chat
_ Command_hidetag is the callback of
Code:
RegAdminCmd("sm_hidetag", Command_hidetag, ADMFLAG_KICK);
that creates the command sm_hidetag for the console and !hidetag, /hidetag, !sm_hidetag and /sm_hidetag for the chat.