Which tag should I use?

[Nirvana]

I use the FreeBSD 6.0 Release-P3.
I don't know which tag should my cvsup use to make my FreeBSD become the
FreeBSD 6.0 stable?

The RELENG_6 or RELENG_6_0?

what is the different with the RELENG_6 and RELENG_6_0?


Thank you for you.