I use the scripts from here, with a little change for getting the whole config http://www.gossamer-threads.com/lists/rancid/users/5454
I had to make a couple of additional modifications to get this to work for me on my SLKWRM0000200 running Fabric OS v6.2.2b.
I had to add the following to the %vendortable array in rancid-fe: 'brocade' => 'brocaderancid',
Then I used "brocade" as the system type in router.db like so: fc-sw03:brocade:up
I also had to change "set avautoenable 1" in brocadelogin since the username that rancid uses has an admin role. If i could figure out how to create a read-only user that would have access to enough info, I'd use that instead.