* First round. All messages should be handled by handler1
*/
ioHandler.addMessageHandler( I4.class, ( MessageHandler ) mockHandler1.getMock() );
ioHandler.messageReceived( session, msg[0] );
ioHandler.messageReceived( session, msg[1] );
ioHandler.messageReceived( session, msg[2] );
/*
* Second round. C1 and C3 messages should be handled by handler1. C2
* messages should be handled by handler2.
*/