Gene, thanks for your help.  I finally seem to be on the track of fixing the
problem.  I completely nuked amanda and let Gentoo rebuild it from scratch,
after providing the ebuild with the proper env vars.  This didn't help, but
it gave me a clean slate.

After that, I rewrote my amanda.conf and disklist files for the affected
configs using the templates provided with the current version of amanda (my
old configs have been in use for about 5 years, through several versions of
amanda, and were somewhat hacked and outdated).  I'm not sure exactly which
parameter(s) made the difference, but a backup of the main local system
seems to be proceeding well.

I note that the Gentoo build defaults to 'localhost' for the server address,
which should _always_ be 127.0.0.1, and hence unambiguous.  I trust the
Gentoo devs implicitly.  IMHO, they're right up there with the Debian
package maintainers in knowledge and experience.  I did, however, use the
FQDN for the server in the ebuild, which I prefer in any event.

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