Trouble setting up gtk-doc: glib-object.h not found

[Jens Pelzetter <jens jp-digital de>]

Hello,

I'm writing an application/library which uses the GObject type system.
To document my code, I want to use gtk-doc, but I've trouble with this.
I've set up gtk-doc, but if I start make, I get the following error message:

libexample-scan.c:5:25: error: glib-object.h: No such file or directory

After this error, there many error messages like these:

/usr/include/glib-2.0/glib.h:30:26: error: glib/galloca.h: No such file
or directory
/usr/include/glib-2.0/glib.h:31:25: error: glib/garray.h: No such file
or directory
/usr/include/glib-2.0/glib.h:32:30: error: glib/gasyncqueue.h: No such
file or directory
/usr/include/glib-2.0/glib.h:33:26: error: glib/gatomic.h: No such file
or directory
/usr/include/glib-2.0/glib.h:34:29: error: glib/gbacktrace.h: No such
file or directory
/usr/include/glib-2.0/glib.h:35:26: error: glib/gbase64.h: No such file
or directory
/usr/include/glib-2.0/glib.h:36:32: error: glib/gbookmarkfile.h: No such
file or directory
/usr/include/glib-2.0/glib.h:37:25: error: glib/gcache.h: No such file
or directory
...

When I look into the libexample-scanner.c file, I saw this line:

#include <glib-object.h>

I think these is the problem. In my source files, the equivalent line
looks like this:

#include <glib-2.0/glib-object.h>

So, what is my error? What changes If have to made?

My OS is Gentoo Linux, with the following version of the libraries and
tools:

glib      : 2.16.5
gtk-doc   : 1.10
pgk-config: 0.23
autoconf  : 2.61
automake  : 1.10.1
make      : 3.81

Best regards,

Jens