Alert Player when MSGing AFK Player

This is a simple suggestion:
I know that when you send msgs to a /afk'ed player that they will only receive the msgs when they come back. However, I think a thing should be added where when a player is msging an afk player, it tells them so that they don't continue spamming them or think that the player is ignoring them.

Example:
Player_1: /afk
Player_2: /msg Player_1 Hey! Are you there?
Server: The specified player is AFK and will not receive your message until they come back.

So yeah, that's it.

 

Already on trellooooo
https://trello.com/c/PuUBWuym/698-afk-message-response