Some external packages (for example, lcms2) come bundled with libtool version 2.4 (in the form of ltmain.sh). However, libtool 2.4 does not work in FreeBSD 10.0, as you can see from this thread: http://lists.gnu.org/archive/html/libtool-patches/2011-01/msg00035.html (issue is that rules written for FreeBSD 1 (!!!) are being run in FreeBSD 10.0).
This causes .so files not to be built in the external packages, and the build to fail.
The tarballs would need to be bundled with at least libtool 2.4.2, which fixes this bug.
As far as I can tell....we don't bundle libtool. This could be wrong but for now I'm closing it as NOTOURBUG - users just have to build libtool themselves.
Apologies if I'm incorrect, I'm not a developer, so if you still see this issue with latest version 4.3.+ set the bug back to UNCONFIRMED and I'll get a second opinion from a developer if you think we do in fact package it. Thanks!