Comment 9 for bug 898845

As far as I know embedded copies in FreeImage "are explicitly intended
to be used in that way". [1]

Also, C&P of Hervé Drolon (FreeImage Project Manager) [2]

"Each FreeImage version is developped, tested and designed to run with a
particular set of third party libraries, each library being configured with
a particular set of options. Each new FreeImage release takes into account
the changes log published by each third party library : this way, the
FreeImage code and it's underlying libraries are always up-to-date
regarding bugs and security issues.
FreeImage provides a very simple API to handle various kinds of bitmaps.
It's provided as a single library (.dll or .so). The fact that it uses a
number of third party libraries is convenient for us, the library
developers, but shouldn't concern the users. We patch the libraries to our
needs, to make optimal use of them."

I prefer use the system libs but I think that should be upstream who
make the change officially
and not us. I do not know if patching FreeImage can break something or
cause unexpected behavior.

But if you want keep thinking that patch FreeImage is a good idea... :-\

[1] http://www.debian.org/doc/debian-policy/ch-source.html#s-embeddedfiles
[2] http://sourceforge.net/tracker/?func=detail&aid=2925458&group_id=11504&atid=111504