cubicweb #15135610 instance app not None: Invalid host/port specified. [validation pending]

Launching with pyramid I get

2016-09-01 10:00:56 - (cubicweb.repository) INFO: sql cache usage: 4/0 (100%)
Traceback (most recent call last):
 File "/usr/local/lib/python2.7/dist-packages/cubicweb/cwctl.py", line 146, in run_arg
   status = cmdmeth(appid)
 File "/usr/local/share/cubicweb/cubes/pyramid/ccplugin.py", line 335, in pyramid_instance
   waitress.serve(app, host=host, port=port)
 File "/usr/local/lib/python2.7/dist-packages/waitress/__init__.py", line 11, in serve
   server = _server(app, **kw)
 File "/usr/local/lib/python2.7/dist-packages/waitress/server.py", line 44, in create_server
   adj = Adjustments(**kw)
 File "/usr/local/lib/python2.7/dist-packages/waitress/adjustments.py", line 278, in __init__
   raise ValueError('Invalid host/port specified.')
 ValueError: Invalid host/port specified.
 instance app not None: Invalid host/port specified.
 Process exited with 8
 INFO - Reloading failed. Waiting for a file to change

host and port information in all-in-one.conf are commented, so should it not get default values ?

priorityimportant
typebug
done in3.24.0
load left0.000
closed by#bc864c80ec36 [twconfig] Set default value for "interface" to 0.0.0.0
patch[twconfig] Set default value for "interface" to 0.0.0.0 [applied]