[PD] undefined symbol: XF86VidModeSetViewPort

[romana]

hi all!

I've Gem configured
--without-gltt --without-avi --without-ieee1394

compiled and installed
but when i try to load it it gives me

/usr/local/lib/pd/extra/Gem.pd_linux: 
/usr/local/lib/pd/extra/Gem.pd_linux: undefined symbol: 
XF86VidModeSetViewPort

i've also installed/

/libxxf86vm-dev

which should be answer to this, isn't it?
do i have to set some paths?

powerpc, debian, kernel 2.6.16.20, xorg 7, mesalibs & -glut local installed

thanks,
romana