Took me forever to get this to work. Had to use the server provided otherwise I wouldn't be able to access the "a" thingy.
I reseted the Kindle to factory settings and then I couldn't access "a" through the Kindle, only through other devices (Mac OSX and iPhone).
I had to turn on and off airplane mode and then I could access it.
works just fine on my Paperwhite 3 G090 G105 Brazilian Portuguese.