Workflow Migration


We are currently using IS 6.0.1 with SP2, Broker 6.0.1 and Workflow 6.0.2.

We are interested to migrate workflow 6.0.2 to 6.1 or 6.1.5 alone.

Question: Is this possible to migrate workflow alone with out migrating IS and Broker?

According to my research i found the following.
We can migrate workflow 6.0.2 to 6.1 along with Broker and IS remains on 6.0.1.
Is this true?

The workflow migration guide didnt specify about other associated components like Broker or IS for migrating workflow 6.0.2 to 6.1.

Please advice.

Anil K Atyam