I browsed through the configure output and everything looks just fine.
According to what I see, the build should be using only what it finds in
/usr/pkgsrc/audio/libvorbis/.buildlink to compile and link.  Was the
problematic build you experienced earlier caused by unusual ld.so.conf,
LD_RUN_PATH, or LD_LIBRARY_PATH settings?  Also, what platform/version
of NetBSD are you running?

	Thanks,

	-- Johnny Lam <jlam@jgrind.org>