... I now remember (sorry that I didn't remember before...) that we had luck in the past contacting the FSF at the address licensing@xxxxxxx. They were positive that "the
LGPL v3 is perfectly suited for C++ template libraries":
http://listengine.tuxfamily.org/lists.tuxfamily.org/eigen/2008/02/msg00008.html
Quote:
>When application developers use such header files whose materials are
>incorporated directly into the object code, they only need to provide
>notice that they're using your library, and include a copy of LGPLv3
>with their application.
So I'm pretty confident that you're out of trouble but feel free to
ask them your more specific questions regarding closed-source software
and the interpretation of sections 0 and 4...