In ipatests/test_xmlrpc/tracker/base.py, methods 'ensure_exists' and 'ensure_missing' are defined. Usage of these methods in other methods, e.g. 'update', causes silent creation or deletion of entries. This practice is discouraged, creation of entries should be handled by programmer himself, not by underlying code.
As part of fix for this ticket all existing tracker based tests should be modified not to use problematic methods.