[GtkGLExt] configure: error: Cannot find GL library

[YuGiOhJCJ Mailing-List <yugiohjcj-mailinglist laposte net>]

Hello,

I am compiling gtkglext 1.2.0 on GNU/Linux DEBIAN "lenny" and I got an error telling "Cannot find GL library".
$ ./configure
[...]
checking for gdk_x11_colormap_foreign_new... yes
checking for X... libraries , headers
checking for gethostbyname... yes
checking for connect... yes
checking for remove... yes
checking for shmat... yes
checking for IceConnectionNumber in -lICE... yes
checking for X11/Xmu/StdCmap.h... yes
checking for Xmu/StdCmap.h... no
checking for XmuLookupStandardColormap in -lXmu... no
checking GL/glx.h usability... yes
checking GL/glx.h presence... yes
checking for GL/glx.h... yes
checking GL/gl.h usability... yes
checking GL/gl.h presence... yes
checking for GL/gl.h... yes
checking GL/glu.h usability... yes
checking GL/glu.h presence... yes
checking for GL/glu.h... yes
checking for glVertex3d in -lGLcore... no
checking for glVertex3d in -lGL... no
checking for glVertex3f in -lGL... no
checking for glVertex3i in -lGL... no
checking for glVertex3s in -lGL... no
checking for glVertex3d in -lMesaGL... no
configure: error: Cannot find GL library

I think I have installed all the packages I need : libgl1-mesa-glx and libglu1-mesa.
$ sudo apt-get install libgl1-mesa-glx libglu1-mesa
Reading package lists... Done
Building dependency tree
Reading state information... Done
libgl1-mesa-glx is already the newest version.
libglu1-mesa is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 18 not upgraded.

What I package forgot?

Thank you a lot.

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