After having fixed the DBD::Pg bug resulting from the faulty Apple Security Update, which necessitated recompiling Postgres and running sudo ranlib /usr/local/pgsql/lib/libpq.a I discovered another bug.
My PostgreSQL was compiled with UTF-8 support, and my DBD::Pg was rebuilt/reinstalled after the Postgres recompile. However, my scripts were still bombing out with:
dyld: perl Undefined symbols:
_is_utf8_string
Trace/BPT trap
This posting speculates at the solution, which happily works:
http://www.geocrawler.com/mail/msg.php3?msg_id=10411736&list=105
Specifically, commenting out the code between the ifdefs in the section that refers to is_utf8_string (circa line 1482 of dbdimp.c), then make clean / make / make install allowed DBD::Pg 1.21 to install OK and stopped perl from crashing out with the above error.
Now, to see if that completely breaks something else…