Buddy showing up as "not authorized"

[Quinn Collard]

One of the chat protocols I use Pidgin for is Jabber, and I have a buddy 
that I've been friends with for almost a year with no trouble. But all 
of a sudden now he's showing up on my buddylist as "Not authorized." The 
only solution I could find googling was that my friend was supposed to 
be able to right-click on me on his own buddylist and find a "Request 
(re)authorization" setting, but he says he doesn't see that. He's not 
using Pidgin, he's using iMessage.