[BioC] how to configure "pkgconfig"

[shen bairong]

Dear friends,

I am installing Rgraphviz to my MAC OS X, I installed
graphviz 2.6 successfuly, when I install Rgraphviz, I
failed.

Since the dotneato-config machenism is replaced by
pkgconfig method if graphviz version <2.4
However, when I configuire
with-graphviz=/usr/local/lib

Configuring alwasy searched for "dotneato-config". I
wish to know how to modify the "configure.in" file and
set the configuring search for "pkgconfig" directory.

Thanks for the help!

Bairong