Greece has a custom domain extension .ελ
I cant add DOMAIN.ελ records in dns using the A or AAAA buttons (when the zone is already made). It wil say "The hostname has the wrong format.".
Also: When the zone is made it will show it as DOMAIN.xn--qxam in the records overview instead of DOMAIN.ελ.
I would expect that it would add a A or AAAA record and not give an error :)
ISPConfig version: ISPConfig 3.1.15p3
I have no problem giving you temporary access to see it.