git bisect not accepting -git kernels

Hi!
I was trying to do a git bisect on 2.6.22-git6 and 2.6.22-git8. For 
which I get following error :
root@amit:/usr/src/linux-git # git bisect good v2.6.22-git6
Bad rev input: v2.6.22-git6

The repository is obtained by :
root@amit:/usr/src # git clone 
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 linux-git

I am running following git version on Debian Sid, updated today.
# git --version
git version 0.99.8.GIT
'# dpkg -l | grep git' shows ' git-core 
1:1.5.2.3-1'

I tried searching man-pages/documentation/website but couldn't find any 
references to git bisect on -git kernels. I would be grateful if anyone 
can help me find what's going wrong.

As I am not subscribed to the mailing-list, please cc me to all the 
messages on the thread.
Thanks and Regards,
-- 
Amit Walambe
Design Engineer, Arcom Control Systems Ltd.
http://www.arcom.com
Tel: +44-(0)1223 411200 ext. 3204
Direct: +44-(0)1223 403465

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