freebsd-stable packages on freebsd-release-4.9

[Clay Holladay]

I upgraded my ports tree with cvsup using "." for the release so I  
would get the latest ports.  pkg_add -r downloads packages from  
freebsd-release-4.9 and portupgrade -aPPR fails because it tries to  
download packages with version numbers matching the ports tree from the  
freebsd-release-4.9 directory.  Compiling from ports give up to date  
software.  I know that ports only supports freebsd-stable and freebsd- 
current, so is this what should be happening?  Or should pkg_add -r be  
in synch with ports.  Is it possible to use freebsd stable packages on  
freebsd-4.9, or do I need to always compile from ports?