I was trying to compile an old KDE 3.5 application this weekend because no port to KDE 4 has yet been made. Judging by the activity on the site, it is doubtful that it ever will be. For the curious, I was trying to get SchafKopf  up and running. I am running Ubuntu 10.04 (Lucid) which has long since ditched the KDE 3.x line for the shiny 4.x line.
While some of the KDE 3 libraries still ship, some key ones for this particular application were missing. Namely, libkdegames. The solution turned out to be the KDE/Trinity project . This project attempts to continue development and maintenance on the 3.x line.
As a sidenote, this is what is so beautiful about open source software. The vendor threw out a line that was beloved of some and replaced it with something they did not like so well. Rather than being stuck, they can maintain the software themselves.
Back to the problem. All that I needed to do was install the libkdegames-kde3-dev package and run:
% ./configure --without-arts --includedir=/opt/kde3/include/kde % make % sudo make install
and everything was cool. --without-arts may or may not have been necessary after installing the trinity libraries. It was earlier. /opt/kde3/include/kde is where the includes were placed, instead of the standard path.