A new parameter has to introduced to be able to work properly with RabbitMQ 3x : frame_max.
http://www.rabbitmq.com/blog/2012/11/19/breaking-things-with-rabbitmq-3-0/
If not given to bunny, the default value will be negociated with the server. This value can be to small for big stasktrace.
I have personnaly experiment the problem.