The reason I could not build, is that there are duplicate .h files in the linux-headers tree and in the linux-wlan-ng tree. By removing the "wlan" and "prism2" directories in /usr/src/linux- headers-2.6.17-6/include I was able to compile the modules (using "sudo module-assistant build linux-wlan-ng").
Of course, the linux-wlan-ng-source 0.2.4+svn20060414-5ubuntu1 still fails to build, but the newer 0.2.4+svn20060808-2 builds. -- prism2 modules won't build on 2.6.17 https://launchpad.net/bugs/53748 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs