Additional info for Robert. For Undernet only, you won't need to stack multiple nicks into the message to all-ops or all-voices, you can instead do:
To all ops:
/notice @#channel message
or
/quote WALLCHOPS #channel message to all ops
To all voices:
/quote WALLVOICES #channel message to all voices
Note that if you use /WALLVOICES without the /quote preceding it, that mIRC is instead sending out /notice +#channel message, because that's what the /version token for STATUSMSG=@+ is promising will work but actually does not work. Also, even though +#channel is supposed to also be visible to everyone having a higher status, at Undernet the WALLVOICES messages cannot be seen by the @ ops unless they give themselves +v too.
