That series of RFCs (1149, 2549, 6214) keeps getting rediscovered by new generations of technical folk. Among other issues that have never been completely addressed are accidental encapsulation of packets in hawks, and whether the Internet is doomed to be slow in locations where the only avian carriers available are flightless.
There has been one successful implementation of the protocol to date. 55% of ping attempts went through.
(As April Fools RFCs go, the only one that’s arguably more popular than IPoAC is the Hyper Text Coffee Pot Control Protocol, the source of 418 I am a teapot).
I think it was supposedly New Zealand or something. It’s been a long time since I’ve read the full texts.