importing multiple active streams into RTC

If the other source control system is ClearCase, then you can use the ClearCase Synchronizer, and it will maintain the relationships. If the other source control system is Subversion, then you can use the Subversion importer. If the other source control system can be imported into Subversion, then you can first import into Subversion, and then import from Subversion into RTC. If none of the above is true, then you'll need to write your own import scripts.

Cheers,
Geoff

I have three or four active streams in a project I am migrating to RTC from another source control system. Are there standard practices for migrating the data while preserving the relationship among the data?