can't connect to http://repo.bukkit.org/content/groups/public

when we try to build some artifacts using the bukkit as dependency, i am getting the below error.

Could not transfer artifact org.bukkit:bukkit:pom:1.4.6-R0.3 from/to bukkit-repo (http://repo.bukkit.org/content/groups/public): repo.bukkit.org: No address associated with hostname
