I've seen an original BSG warrior jacket up close and I remember that it has an extra layer inside under the lining that gives it the stiffness. I've yet to see a replica jacket done that way. Now that would be cool and accurate.
Its not just the fabric lining, it uses a couple of different stiffening agents that interfaces between the liner. I was very surprised myself with the jacket and also the shirt and pant stiffness as well!