Bukkit/CraftBukkit — pull request #677 by AlphaBlend (2012-02-21 06:10:41+00:00)
Title: When logging in more than once, the duplicate login is kicked without any extra processing

This is my proposed fix to the problem of logging a player in more than once. This pull request is complimentary of my JIRA issue here: https://bukkit.atlassian.net/browse/BUKKIT-761