Darkfall: Unholy Wars Executive Producer 'Zad' has posted a short notice on the official forums to let players know that the game servers will be shut down effective immediately. Aventurine is hopeful that this is only a temporary service disruption but only time will tell.
We have been involved with Darkfall for over 13 years now and it is our hope that we will be able to continue well into the future with your support. Unfortunately, and against our best efforts, the conditions in Greece have caught up with us and do not allow us to continue operating the game as we have been so far. We hope that the disruption of Darkfall Unholy Wars service is temporary and that we will be back soon in a more sustainable format. We apologize for the inconvenience to all that are affected.
Source: This MMORPG.com forum thread (thanks, treyu86!) and Darfall: Unholy Wars forum