[wmx] Compiling error with wmx6

Hi to you all,

I used to work with wmx 5, and I liked it very much.

Now I want to use wmx 6 but I cannot compile it...
Here is the error message :

c++ -o wmx Border.o Buttons.o Channel.o Client.o Config.o Events.o 
Main.o Manager.o Menu.o Rotated.o Session.o -L/usr/X11R6/lib -lXext -lX11
Border.o: In function `Border::initialiseStatics(WindowManager *)':
/home/nico/wmx-6/Manager.h:36: undefined reference to `XpmReadFileToPixmap'
/home/nico/wmx-6/Manager.h:36: undefined reference to 
`XpmCreatePixmapFromData'
collect2: ld returned 1 exit status
make: *** [wmx] Error 1
[nico@nico wmx-6]$

Do you know what's happening ? I'm not a developer, but I know how to 
edit files...
I have a Mandrake 8.0, with kernel 2.4.3 and XFree86 4.0.3.
And it seems that all the libs needed are in /usr/X11R6/lib/.

Thank you very much for your help !

Nicolas
Boulogne-Billancourt (France)