If you are getting error 503 (or any other very rare/unusual error consistantly) when trying to log into VC, or any server for that matter, it is because a group of hackers found an exploit in the Minecraft server authentication code, and were able to log in as whoever they wanted to, whether it was Notch or the admin of a server.
To protect Minecraft servers, Mojang has shut down their authentication server, which means you can't log in to any server that requires authentication, which is most servers, which includes VillageCraft.
If the problem is long-term, we will back up the server on a hard drive, turn off authentication and let everyone play. In an extreme case, if VC is attacked, we will shut down the server, and give you updates from here or from the VillageCraft Steam group
http://steamcommunity.com/groups/village-craft. The problem will probably be short-term though, and you will be playing before you even read this. Lets see.
http://www.reddit.com/r/Minecraft/comments/wl0zy/psa_exploit_in_minecraft_login_server_hackers_can/https://twitter.com/notchhttp://www.mojang.com/Good night.
-Akomine
Update September 9th 2012: this apparently happened again tonight. The authentication server is down - I do not know if it was hacked again or what.