Aptitude Not Using Packages From Volatile

["Jason Self" <jason.self@gmail.com>]

I'm using Debian Sarge 3.1r1. After adding deb
http://volatile.debian.net/debian-volatile sarge/volatile main into
sources.list, I ran apt-get update, which returned:

Hit http://linux.csua.berkeley.edu stable/main Packages
Hit http://linux.csua.berkeley.edu stable/main Release
Hit http://linux.csua.berkeley.edu stable/main Sources
Hit http://linux.csua.berkeley.edu stable/main Release
Hit http://security.debian.org stable/updates/main Packages
Hit http://security.debian.org stable/updates/main Release
Hit http://volatile.debian.net sarge/volatile/main Packages
Hit http://volatile.debian.net sarge/volatile/main Release
Hit http://debian.oregonstate.edu stable/main Packages
Hit http://debian.oregonstate.edu stable/main Release
Hit http://debian.oregonstate.edu stable/main Sources
Hit http://debian.oregonstate.edu stable/main Release
Reading Package Lists... Done

and entered "aptitude install spamassassin" and ended up with version
3.0.3 from stable. I can't figure out why.

/etc/apt/preferences does not exist to override anything.

/etc/apt/sources.list contains:

deb http://debian.oregonstate.edu/debian/ stable main
deb-src http://debian.oregonstate.edu/debian/ stable main

deb http://linux.csua.berkeley.edu/debian/ stable main
deb-src http://linux.csua.berkeley.edu/debian/ stable main

deb http://security.debian.org/ stable/updates main

deb http://volatile.debian.net/debian-volatile sarge/volatile main


apt-cache policy returns:

Package Files:
 100 /var/lib/dpkg/status
     release a=now
 500 http://volatile.debian.net sarge/volatile/main Packages
     release o=volatile.debian.net,a=sarge,l=debian-volatile,c=volatile/main
     origin volatile.debian.net
 500 http://security.debian.org stable/updates/main Packages
     release v=3.1,o=Debian,a=stable,l=Debian-Security,c=updates/main
     origin security.debian.org
 500 http://linux.csua.berkeley.edu stable/main Packages
     release v=3.1r1,o=Debian,a=stable,l=Debian,c=main
     origin linux.csua.berkeley.edu
 500 http://debian.oregonstate.edu stable/main Packages
     release v=3.1r1,o=Debian,a=stable,l=Debian,c=main
     origin debian.oregonstate.edu
Pinned Packages:


apt-cache policy spamassassin returns

spamassassin:
  Installed: 3.0.3-2
  Candidate: 3.0.3-2
  Version Table:
 *** 3.0.3-2 0
        500 http://debian.oregonstate.edu stable/main Packages
        500 http://linux.csua.berkeley.edu stable/main Packages
        500 http://security.debian.org stable/updates/main Packages
        100 /var/lib/dpkg/status