[44net] Getting no response from 251.66.228.169

Hello i am sysop of OK2KOJ-5 gateway in Brno, Czech Rep. The gateway has known amprIP 44.177.10.253 and public IP 176.74.143.164 hostname ok2koj.ddns.net. I registered this gateway here for the encap table. I have run on OK2KOJ the ampr-rip program with proper tunl0 interface but there is no response packets from amprnet server 251.66.228.169 (port 520 is open). I use appropriate text password which I put in text into registration of that gateway. The problem is that I don't know how to get coded string of that text password. So I think that is the problem why I do not get response from amprnet server. How can I get that text password in coded form? Thank you for help Dalibor P.S. I am laso sysop of OK2PEN-5 gateway (44.77.10.10) where I get successfull response from amprnet gateway.