cubicweb-trustedauth #1480189 trustedauth breaks Pyro cw-shell [deprecated]

Trying to use cw-shell to access a remote instance using trustedauth crashes:

adim@esope:~$ cubicweb-ctl shell -P -H cepheus jpl
login: adim
password:
Traceback (most recent call last):
  File "/home/adim/bin/cubicweb-ctl", line 4, in <module>
    run(sys.argv[1:])
  File "/home/adim/src/fcube/cubicweb/cwctl.py", line 969, in run
    CWCTL.run(args)
  File "/home/adim/src/fcube/logilab/common/clcommands.py", line 128, in run
    sys.exit(command.main_run(args, rcfile))
  File "/home/adim/src/fcube/logilab/common/clcommands.py", line 254, in main_run
    self.run(args)
  File "/home/adim/src/fcube/cubicweb/cwctl.py", line 872, in run
    cnx.load_appobjects()
  File "/home/adim/src/fcube/cubicweb/dbapi.py", line 543, in load_appobjects
    self.vreg.register_objects(vpath)
  File "/home/adim/src/fcube/cubicweb/cwvreg.py", line 651, in register_objects
    path, self.config.extrapath)
  File "/home/adim/src/fcube/cubicweb/vregistry.py", line 411, in register_objects
    self.load_file(filepath, modname)
  File "/home/adim/src/fcube/cubicweb/vregistry.py", line 467, in load_file
    self.load_module(module)
  File "/home/adim/src/fcube/cubicweb/vregistry.py", line 472, in load_module
    module.registration_callback(self)
  File "/home/adim/src/fcube/cubes/trustedauth/entities.py", line 27, in registration_callback
    secret = open(vreg.config.get(CONFENTRY, "")).read().strip()
IOError: [Errno 2] No such file or directory: ''
prioritynormal
typebug
done in<not specified>
load0.000
load left0.000
closed by<not specified>