       author = self.getAuthorFromRequest req
       author = self.robot.brain.userForId author.id, author
       author.room = req.param 'channel_name'
-      author.reply_to = req.param 'channel_id'
+      author.reply_to = undefined
+      self.channelMapping[author.room] = req.param 'channel_id'
 
       if hubotMsg and author
         # Pass to the robot

https = require 'https'

class Slack extends Adapter
  ###################################################################
  # Slightly abstract logging, primarily so that it can
  # be easily altered for unit tests.

    #
    # Note: Slack's API here uses rooom ID's, not room names. They look
    # something like C0capitallettersandnumbershere
    params.reply_to ||= @channelMapping[params.room]

    params

