[sigc] License Problems

[Marius Elvert <st_jax web de>]

Hello!
I stumbled across a legal traphole in libsigcs license today.
The agenda on the license page clearly states that libsigc is meant to 
be used in "all projects both open and proprietary", however a detail in 
the LGPL license makes this nearly impossible.
Section 5 paragraph 3 states that 'When a "work that uses the Library" 
uses material from a header file that is part of the Library, the object 
code for the work may be a derivative work of the Library even though 
the source code is not.'
This concerns libsigc++, because major parts of the implementation are 
in the header files and are therefore compiled into the object files of 
programs that are, from a programmers point of view, only using the 
library. Hence the license forces you do opensource everything that uses 
libsigc.
I think this is not intended and originates in the fact that templates 
are not compiled into object code before actually instancing them.

-MElvert