extattr-2.diff, 118K, sha1
c81f377d9f4a630f873f0bda82bad06852dde1e2
extattr-3.diff, 152K, sha1
7f1b369ce0aa3546b4c36201d0a5f060a591ec39 (has dump/restore support)
Apply the diff, go to src/sys/kern, type 'make' and follow the standard 'make build' procedures.