I have the same issue with the CLI on unconditional call forwarding being set to the original caller's number as in this post from March 2012 http://lists.sipwise.com/pipermail/spce-user/2012-March/001149.html

In that post it suggests that version 2.6 might have a fix. I am on 2.8 and have tried various settings but can't see a way to make the From: header contain the subscriber's CLI.

Is this still not possible without a custom tweak?