Unexpected exception from downstream.java.io.InvalidClassException: failed to read class descriptor (NETTY)
Environment 
Client / Server using Java 
Java = 1.6 (Update 31)
Netty = 3.5.2 - Final
I Am quite new to using Netty, and am trying out the basics first,  i.e. send a String or Date from my client to my server, now I can get this to work, and can use “instanceof”  to detect a string or date, and output as appropriate but when I extend this to use my own simple class, I am getting a error (see title and code below), I have looked at the pingpong example on netty documentation, so I think I am missing something, (may be small or very large), so some pointers in the right direction would be nice  

    Error Dump

    23-Jul-2012 17:37:19 clsNetworkServerHandler exceptionCaught
    WARNING: Unexpected exception from downstream.
    java.io.InvalidClassException: failed to read class descriptor
	at java.io.ObjectInputStream.readNonProxyDesc(Unknown Source)
	at java.io.ObjectInputStream.readClassDesc(Unknown Source)
	at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
	at java.io.ObjectInputStream.readObject0(Unknown Source)
	at java.io.ObjectInputStream.readObject(Unknown Source)
	at org.jboss.netty.handler.codec.serialization.ObjectDecoder.decode(    
Unexpected exception from downstream.java.io.InvalidClassException: failed to read class descriptor (NETTY)
===

Environment 
Client / Server using Java 
Java = 1.6 (Update 31)
Netty = 3.5.2 - Final
I Am quite new to using Netty, and am trying out the basics first,  i.e. send a String or Date from my client to my server, now I can get this to work, and can use “instanceof”  to detect a string or date, and output as appropriate but when I extend this to use my own simple class, I am getting a error (see title and code below), I have looked at the pingpong example on netty documentation, so I think I am missing something, (may be small or very large), so some pointers in the right direction would be nice  

    Error Dump

    23-Jul-2012 17:37:19 clsNetworkServerHandler exceptionCaught
    WARNING: Unexpected exception from downstream.
    java.io.InvalidClassException: failed to read class descriptor
	at java.io.ObjectInputStream.readNonProxyDesc(Unknown Source)
	at java.io.ObjectInputStream.readClassDesc(Unknown Source)
	at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
	at java.io.ObjectInputStream.readObject0(Unknown Source)
	at java.io.ObjectInputStream.readObject(Unknown Source)
	at org.jboss.netty.handler.codec.serialization.ObjectDecoder.decode(    