This is the OpenBSD-enhanced version of the original PD-ksh, which in turn is a clone of the original AT&T Korn shell.
This version is based on the porting work of Jason Wright and Marco Peereboom, and has everything the OpenBSD 5.3 version has. Tom Murphy contributed diffs to make bulding possible on FreeBSD.
openbsd-ksh-5.3.tar.gz
MD5 (openbsd-ksh-5.3.tar.gz) = e2e6ad670600fd05f5bf6c78dca861a3
The binary packages are gone. Just build the thing from sources. Control files to build both .debs and .rpms are included.