SendAddonMessage to Channel not working

[hamunaptra]

As a followup to my previous post about sending messages around...

It seems that using SendAddonMessage with a custom channel doesn't work (or I'm doing something totally wrong).

If I send a message with SendAddonMessage to a party, it works fine, but if I do it to a (custom) channel, nothing get's received.

Sample project attached. What am I doing wrong? It looks right...

SLASH_ZSCT1 = "/zsct"

SlashCmdList["ZSCT"] = function(msg)
    print("Sent message through party ...")
    C_ChatInfo.SendAddonMessage(prefix, "sent using party")
    print("Sent message through channel (" .. channelid .. ") ...")
    C_ChatInfo.SendAddonMessage(prefix, "sent using channel", "CHANNEL", channelid)
end

local function zSendChatTest_EventHandler(self, event, pre, msg, distribution, sender)
    if pre == prefix then
        print("Received message " .. msg)
    end
end

channelname = "zsendchattest"
prefix = "zsendchattest"
password = "secret"

JoinChannelByName(channelname, password)
channelid = GetChannelName(channelname)

C_ChatInfo.RegisterAddonMessagePrefix(prefix)

zSendChatTest_Frame = CreateFrame("Frame")
zSendChatTest_Frame:SetScript("OnEvent",  zSendChatTest_EventHandler)
zSendChatTest_Frame:RegisterEvent("CHAT_MSG_ADDON")

print("ZSCT Loaded")

Results:
Client 1 ("master")


Client 2 ("slave")