class WEBrick::HTTPResponse

through WEBrick::HTTPResponse if rack is set to true.
This monkey patch allows for applications to perform their own chunking

def setup_header 

def setup_header
  app_chunking = rack && @header['transfer-encoding'] == 'chunked'
  @chunked = app_chunking if app_chunking
  _rack_setup_header
  @chunked = false if app_chunking
end