But SA doesn't seem to be checking the RBLs.
I've looked at the page at http://wiki.apache.org/spamassassin/UsingNetworkTests
But my /etc/rc.d/init.d/spamassassin file doesn't cntain the -L or --local entries anywhere
Do you have Net::DNS installed?
try running spamassassin --lint -D and see what SA has to say about DNS availability.