Redmine

Environment:
Redmine version 2.3.2.stable
Ruby version 1.9.3-p448 (2013-06-27) [x86_64-linux]
Rails version 3.2.13
Environment test
Database adapter Mysql2
Redmine plugins:
redmine_charts2 0.2.1
scrum2b 0.1
status_button 0.1.0

Above the base configuration:

After i've started the script with the command " rake redmine:migrate_from_mantis RAILS_ENV="test" " i recieved the following report:

Migrating users
Migrating projects.............................................................................................................
Migrating bugs
Migrating bug relations
Migrating news
Migrating custom fields......

Users: 0/0
Projects: 109/110
Memberships: 0/0
Versions: 57/57
Categories: 313/376
Bugs: 0/661
Bug notes: 0/7329
Bug files: 0/856
Bug relations: 0/339
Bug monitors: 0/378
News: 0/1
Custom fields: 6/6

As you can see, the script doesn't consider any bugs. Has anybody any idea? Do you need any further information for analyzing?
Thanks in advance.