Hello Mike,
i've configured it with the EC2 autodiscovery, but i didn't run out of the box. Both machines could resolve eacht other and i see that the they try to communicate but the connection got lost. I think that was a issue with the "auto port increase" or something. i thing its possible to run it with aws autodiscovery config, but the normal configuration with the IP Adresses was enough for me(for the first step). I will work on that problem if i decide to use openfire.it looks good so far :-) .
By the way, your hint was correct to use the IP Adress instead of DNS. But i had an other problem a this time, so it doesn't solved my problem. No it works!
Thank's