Which ports tree through svn?

[Andrei Brezan]

Hello list,

I'm using:
FreeBSD myhost.mydomain.com 9.0-RELEASE-p3 FreeBSD 9.0-RELEASE-p3 #0: 
Tue Jun 12 02:52:29 UTC 2012 
root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC amd64

I want/need to use svn for my ports tree mainly because I need to 
downgrade ports. There is portdowngrade in the ports tree but that 
relies on cvs which is no longer available. The only way that I'm able 
to do this now is with svn log and svn up -r to the revision needed so I 
get the version that I need in the port.

My problem is what do i need to checkout in the first place for 9.0-RELEASE?
svn co svn://svn.freebsd.org/ports/head /usr/ports or svn co 
snv://svn.freebsd.org/tags/RELEASE_9_0_0 /usr/ports?

The first one seems to be up to date but the latter has for eg apache 
version 2.2.21 from 2011; I presume from the portfreeze before 9 was 
released.

Maybe there are any means to downgrade ports while using portsnap that 
I'm not aware of.

Thank you,
Andrei