If you create a user in Katello that has utf8 characters in the username and then attempt to interact with pulp with syncs, repo discovery or anything that requires delayed task processing you will see errors in Katello and Pulp.

How to reproduce (create a user, a repo and sync):

katello -u admin -p admin user create --username "Mané" --password redhat --email "mane"
katello -u admin -p admin user assign_role --username "Mané" --role "Administrator"
katello -u Mané -p redhat org create --name Cuiabá --label Cuiaba
katello -u Mané -p redhat provider create --name test_prov --org Cuiabá
katello -u Mané -p redhat product create --name Cuiabá_prod --provider test_prov --org Cuiabá
katello -u Mané -p redhat repo create --name Cuiabá_repo --product Cuiabá_prod --org Cuiabá --product Cuiabá_prod
katello -u Mané -p redhat repo synchronize --name Cuiabá_prod_dummy_repos_zoo --org Cuiabá --product Cuiabá_prod

Error in pulp log:

2012-10-01 10:48:16,450 11917:140154905814784: pulp.server.webservices.controllers.repositories:INFO: repositories:1179 sync timeout passed : None
2012-10-01 10:48:16,500 11917:140155184740096: pulp:CRITICAL: queue:130 Exception in FIFO Queue Dispatch Thread
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/pulp/server/tasking/taskqueue/queue.py", line 124, in _dispatch
    self.run(task)
  File "/usr/lib/python2.6/site-packages/pulp/server/tasking/taskqueue/queue.py", line 314, in run
    self.__storage.store_running(task)
  File "/usr/lib/python2.6/site-packages/pulp/server/tasking/taskqueue/storage.py", line 232, in store_running
    self._snapshot_task(task)
  File "/usr/lib/python2.6/site-packages/pulp/server/tasking/taskqueue/storage.py", line 223, in _snapshot_task
    snapshot = task.snapshot()
  File "/usr/lib/python2.6/site-packages/pulp/server/api/repo_sync_task.py", line 64, in snapshot
    snapshot = super(RepoSyncTask, self).snapshot()
  File "/usr/lib/python2.6/site-packages/pulp/server/tasking/task.py", line 314, in snapshot
    snapshot = model.TaskSnapshot(data)
  File "/usr/lib/python2.6/site-packages/pulp/server/db/model/persistence.py", line 45, in __init__
    self.update(self._process_serialized_task(serialized_task))
  File "/usr/lib/python2.6/site-packages/pulp/server/db/model/persistence.py", line 58, in _process_serialized_task
    return dict([(k, _process_value(v)) for k, v in serialized_task.items()])
  File "/usr/lib/python2.6/site-packages/pulp/server/db/model/persistence.py", line 55, in _process_value
    value = value.decode('utf-8')
  File "/usr/lib64/python2.6/encodings/utf_8.py", line 16, in decode
    return codecs.utf_8_decode(input, errors, True)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xe9 in position 270: invalid continuation byte