Git tags

Hi all,

I don't really know where to post this question. Why, if I check out the 
2.6.24.4 kernel (2.6.24.4 tag 
http://git2.kernel.org/?p=linux/kernel/git/stable/linux-2.6-stable.git;a=commit;h=16c64cac7d9c6a503f49887219c4fe675e7d43d9) 
from the stable git tree, I get "dirty" added to my kernel version after 
compilation? The 2.6.24.4 is stable as far as I understand.
I have already searched for this info and looked through some tutorials 
like http://linux.yyz.us/git-howto.html, but I didn't find any info that 
would answer my question.

Thank you  in advance.

Best regards,
Yegor