MinecraftForge/FML — pull request #355 by jk-5 (2014-01-19 10:23:26+00:00)
Title: Throw an exception when discriminator is not found

Instead of letting it fail 1 line lower with a NullPointerException, which will be thrown as a netty DecoderException, be informative to the user, which discriminator is missing and in which channel.