Rebase v.s. fast forward

I am dealing with a kernel branch of a branch that undergoes frequent
rebases and I want to know the easiest way of handling things.

The tree is pulled from kernel.org. Patches are applied to the tree by a
developer here on a branch.  I take that branch, make my own branch, add
drivers and other modifications and publish to a different repo.

Now that 2.6.29 is occurring, every time there is a new RC candidate, he
rebases the tree and tells everyone to rebuild.  Since the developers on
my projects have their own branches off of my tree, rebuilding
everything is starting to look like a big pain.

Is there a way to take a rebased repository and apply the changes in a
manner that does not require reconstructing everything from patches?

Can you fast forward on a rebased repo or are you just hosed?  (Or would
that be considered "frebasing"?)