[boost] [fsm] Accessing a state instance in a state machine?

I had a quick look at the documentation of the Boost FSM library as I need to implement a simple protocol handler for a network application. The protocol handler sends and receives text messages and switches between various states. What I wonder is how I can pass for example a reference to a socket to a state so that the state can send a text message? There doesn't seem to be a way to acccess a state instance in a state machine? Boris