It appears you solved your own problem, so I won't try to get into it. One suggestion though, that a number of admins seem to prefer, is to make your own custom changes in local.cf rather than any of the other cf files. This is not necessary, as all cf files in the /opt/zimbra/conf/spamassassin path are read and implemented, but the advantage is that local.cf overrides any other file, so if you keep all your customizations there, you have only one file to backup and restore if your system blows up, or when you upgrade to a new version.
I say the latter of these two because all your spamassassin configuration files will be overwritten any time you upgrade Zimbra versions. Although you should backup your entire Zimbra database before any upgrade, I still prefer to restore only local.cf because I don't want to lose any other improvements that might be part of the upgrade in other files.
Cheers,
Dan |