trac2youtrack: Milestone Field unknown

Hi,

I'm currently trying to migrate a Trac installation to YouTrack, assisted by the Documentation. There were a few issues I was able to resolve by updating the Trac database, but now I reached a point where I got stuck.

The importer fails to import most of the issues, specifically ones that have a Milestone attached. The migrator log is full of messages like this:

• Failed to import issue [ TRACIMP-1384 ].Reason : <item id="1384" imported="false"><error fieldName="Milestone">Field is unknown</error></item>Request was : <issue>

I'm under the impression that Milestones are a core part of Trac and I don't need to change the mapping file for them to be imported. It appears that the importer does something with the milestones at the begin of the import, I'm getting this message for every milestone:

• Value with name [ <Milestone> ] already exists in bundle [ TRACIMP: Versions ]

I'm stumped. Does anyone have an Idea why the Milestones don't appear to be recognized correctly?

I appreciate your assistance. Let me know if you need some more information.