There is a pull request that covers it. However, it isn't implemented yet for the official server. You could take the source from the pull request and include it in your .jar file, as it is a stand-alone file.
Is this a planned feature to be incorporated into the Bukkit core? Seems like it would almost be essential.
Just saw that this is implemented since i dont know when ^^ Player.getTargetBlock() http://javadoc.lukegb.com/Bukkit/d4...Entity.html#a889b8d9fb7d4a9ad042392a1cdd7e284