Quote Originally Posted by 'Macaroon',index.php?page=Thread&postID=197950#pos t197950
One of the Ace core libraries provides the /in command. If you use an Ace addon, you have the /in command. Blizzard does not supply such a command.
I do have a couple ace addons so that must be it. I still can't find a reference to it anywhere, which is why I thought it was built in.