Exposing internal functions

[Jose]

Hello.

I need to use one internal function from octave, specifically __fdjac__.

In order to do so I can:
1- Copy it from its original directory to anywhere in octave's path.
2- Create a symbolic link from anywhere in octave's path pointing to the 
real file.

Neither of the previous methods will survive a new octave installation 
in a new directory. I wonder if there is a better way to do it so that I 
don't have to care about doing this every time that I install a new 
version of octave, e.g. adding something to octaverc.

Br,
Jose