Ran into a permission problem with Permissions 3.1.5b, odd and unable to reproduce -- had a user group's permissions defined as and said group...
I'll give the mods / plugin developers a break ;) Link: http://forums.bukkit.org/threads/when-will-bukkit-be-updated-for-minecraft-1-6.18714/
Correct, they would need to rollback their client version.
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