Astrolabe bug?

[myrroddin]

I see change logs for various AddOns saying that they are switching to a different API in TomTom to work around a bug in Astrolabe. The API now being used starts on line 879 of TomTom.lua

function TomTom:AddMFWaypoint(m, f, x, y, opts)

My questions are:

1. What is the nature of the bug in Astrolabe? What was the code supposed to do, and what is it doing instead?
2. Where in Astrolabe's code is the bug found? Which API, Lua file, line number?
3. Why does using TomTom's API bypass the bug?
4. Does Esamynn know?

Thank you for any help.