LINUX: problems compiling SDL 1.0.8

I am getting the following error:

/usr/i486-linux/bin/ld: cannot open -lXxf86vm: No such file or directory

and a similar one for xf86dga. I do have header files that have something to
do with this but apparantly I am missing some libraries. Do I have to get
seperatly somewhere? I couldn’t find them on XFree86 Org.

PS: I am on Slackware Linux and it’s is not a very recent distro.