OpenBSD 5.8 radical CalDAV/CardDAV installation

pkg_add -iv radicale
with auth htpasswd radicale does not start

what is missing?

/usr/local/lib/python2.7/site-packages/radicale # python2.7 -m radicale                               
Starting Radicale
Authentication type is htpasswd

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/runpy.py", line 162, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/local/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/usr/local/lib/python2.7/site-packages/radicale/__main__.py", line 191, in module
    run()
  File "/usr/local/lib/python2.7/site-packages/radicale/__main__.py", line 133, in run
    make_server(address, port, Application(),
  File "/usr/local/lib/python2.7/site-packages/radicale/__init__.py", line 133, in __init__
    auth.load()
  File "/usr/local/lib/python2.7/site-packages/radicale/auth/__init__.py", line 43, in load
    "auth.%s" % auth_type, globals=globals(), level=2)
  File "/usr/local/lib/python2.7/site-packages/radicale/auth/htpasswd.py", line 33, in module
    import bcrypt
ImportError: No module named bcrypt

pkg_add -iv py-bcrypt

later on...

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/wsgiref/handlers.py", line 85, in run
    self.result = application(self.environ, self.start_response)
  File "/usr/local/lib/python2.7/site-packages/radicale/__init__.py", line 289, in __call__
    is_authenticated = auth.is_authenticated(user, password)
  File "/usr/local/lib/python2.7/site-packages/radicale/auth/htpasswd.py", line 80, in is_authenticated
    return globals()["_%s" % ENCRYPTION](hash_value, password)
  File "/usr/local/lib/python2.7/site-packages/radicale/auth/htpasswd.py", line 68, in _bcrypt
    return bcrypt.checkpw(password, hash_value)
ValueError: Invalid hashed_password salt

py-bcrypt has problems with $2b$ hashes :(