Problem: Installing UCS5 errata 881 in a mixed environment breaks UDM


Following the installation of UCS5 errata 881 in a mixed UCS4 and UCS5 environment, the functionality of UDM (Univention Directory Manager) breaks. This issue stems from Bugfix 56824, which inadvertently registers UDM modules domain-wide. Consequently, this registration introduces new code files across all servers, irrespective of their version, resulting in incompatibility with UCS4 systems.

When accessing the UCS4.4-9 system, the following error may occur:

# /usr/share/univention-directory-manager-tools/univention-cli-server                                                                  
Traceback (most recent call last):
  File "/usr/share/univention-directory-manager-tools/univention-cli-server", line 45, in <module>
    import univention.admincli.admin
  File "/usr/lib/python2.7/dist-packages/univention/admincli/", line 57, in <module>
  File "/usr/lib/python2.7/dist-packages/univention/admin/", line 123, in update
    _walk(root, w_root, w_files)
  File "/usr/lib/python2.7/dist-packages/univention/admin/", line 110, in _walk
    m = importlib.import_module('univention.admin.handlers.%s' % (modulepackage,))  # type: Any
  File "/usr/lib/python2.7/importlib/", line 37, in import_module
  File "/usr/lib/python2.7/dist-packages/univention/admin/handlers/saml/", line 195, in <module>
    mapping.register('Identifier', 'SAMLServiceProviderIdentifier', None, univention.admin.mapping.ListToString, encoding='ASCII')
TypeError: register() got an unexpected keyword argument 'encoding'


To resolve this issue on the UCS4.4-9 server, follow these steps:

  1. Reinstall the previous package univention-saml-schema:

    apt-get install --reinstall univention-saml-schema
  2. After the reinstallation, execute the following file to verify proper functionality:


This should rectify the compatibility issue caused by the introduction of incompatible code files on UCS4 systems.