FreeBSD broke with autoconf-based build

I'm having troubles building postgis HEAD on freebsd
using the new autoconf-based scripts.

The Makefile.shlib file copied by pgsql sources
adds a -Bforcearchive flag to LINK.shared with
arch is freebsd, but the flag seems to be
unsupported (this is from 7.2.1 to 8.0.0)

Weird enough PostgreSQL build works fine
(no -Bforcearchive flag used)

If I remove the -Bforcearchive flag from Makefile.shlib
everything seems to work fine.

I suppose (but didn't test) that this would also fail with
pgxs.  Are there freebsd users around to test this ?

--strk;