MessageToByteEncoder's output ByteBuf runs out of space
The MessageToByteEncoder's ByteBuf passed into the encode method quickly runs out of space when a lot (about 100K) of messages are sent in short bursts. See below:

![netty runs out runs out of space](https://f.cloud.github.com/assets/692396/21046/f8820a72-497b-11e2-99d7-950bf066e06b.png)

It is also not possible to increase the buffer's capacity since the capacity(int) method throws an "IllegalArgumentException" if this is attempted.

Before I was simply doing out.writeBytes(...), I started using out.writebytes() followed by ctx.flush() but this only delayed it as the buffer still got backed up.

This only started happening recently after pulling all the latest changes from master
