Just as an update I have everything running great now. Editing the various config files and amavisd is confusing and irritating with the 127.0.0.1 issue, but by no means impossible. My major stumbling block was failing to notice my vserver didn't have cron installed.
woops.
Once I realized that an upgrade to 4.0.3 installed all the necessary cron jobs and I now have server status and the pretty little graphs all working after following the rest of the instructions in this thread.