I'm working on Slackware 8.1/9.0.
You'll first need to satisfy the dependencies listed on the Software Requirements
section of the manual. Some of these probably are installed by default on Slackware, others you'll need to look for on Slackware's site, or the project's site.
After you have the dependencies installed, try running the configure script and let us know how it works. If you run into any problems getting the dependencies, with the configure script or compilation, please reply and we'll try to help you fix them.