I've built and installed the latest tarball:
./configure --prefix=/usr/local ...
And after much guessing I found something that looks like a kernel module:
/usr/local/lib/openafs/libafs-2.4.20.o
But what now?
http://www.openafs.org/doc/index.htm mentions an init script
afs.rc that doesn't appear to be in the source tree or in /usr/local.
-chris