Receiving Messages in python

Is there a way to revive Messages in python similar to the GameLogic.sendMessage function?

You need to receive the message when it is sent, using a receive message sensor. Or you could have an object that receives messages with a rec sensor and stores them in the golbal dict for later recovery…

I’ve never heard of the “rec” sensor, could you tell me about it? And I am using blender 2.49b if it matters.