When you run the tests of SpamAssassin 3.0.0 on Solaris (SPARC or x86) the host may suddenly be renamed to "--fqdn"
The tests that cause this to happen are t/dnsbl and t/spf, which both use the Sys::Hostname::Long class in perl.
This problem is filed in the SpamAssassin Bugzilla: http://bugzilla.spamassassin.org/show_bug.cgi?id=3806
Fix this by running "hostname foo" (as root) to rename you system back to "foo" (or whatever name it should have).
The change is not harmful, the only side-effect is that messages processed by SpamAssassin may produce strange header strings like:
X-Spam-Checker-Version: SpamAssassin 3.0.0 (2004-09-13) on --fqdn
This is caused by a bug in the perl class Sys::Hostname::Long. The bug has been recognized by the Perl developers. The non-POSIX utility "hostname" will not recognize the "--fqdn" switch on Solaris, but will instead interpret it as the argument for a new hostname and renames the host accordingly. (The switch is intended to retrieve the "fully qualified domain name", e.g. "foo.bar.org" instead of just "foo".)