(cogito) Branch offf from older commit?

Is there (in cogito) a way to start a branch off from an older commit?

Assume I receive a patch whichis based on an old version which I want to test first (and resolve problems) in a separate branch.

This was what I tried:

* Clone main repo:
	-> cg-clone /git/u-boot u-boot-testing 
* Identify wanted branch point and seek to it:
	-> cd u-boot-testing
	-> cg-seek 024447b186cca55c2d803ab96b4c8f8674363b86
* Apply patch

Now how to proceed?

I can add new files created by the patch using "cg-add", but cg-status says "Changes recording BLOCKED: seeked from master", and cg-commit says "committing blocked: seeked from master", too.

However, when I now seek back I get this:

	-> cg-seek
	Warning: uncommitted local changes, trying to bring them along

which then results in a couple of conflicts which are probably to be expected.

So I tried this (after throwing away and re-creating my cloned repo):

* Uncommit the commit following the one I want to keep:
	-> cg-admin-uncommit 342717f72a2f92a14b9c823546e5bcec244f8bf4
	-> cg-reset
* cg-status reports a couple of unknown files (those added later to
  the tree); I manually removed these
* Apply patch
* Check in modifications
* Clone another tree
	-> cg-clone /git/u-boot u-boot-test-merge
	-> cd u-boot-test-merge
* Create branch for the stuff to be tested
	-> cg-branch-add testing-NAND /work/u-boot-testing
* Pull and merge:
	-> cg-pull testing-NAND
	-> cg-merge testing-NAND

This works as intended, but seems to be a bit circuitous to me; I think this is probably a pretty common situation and there might be a simpler approach which I am missing?

[If possible I'd like to use cogito only, but if there is a clever way to do this using git-core commands I'm interested, too.]

Best regards,

Wolfgang Denk