Which Package Manager?

I came across a number of apparent tarballs of OS packages which are in a format which I do not recognize. Does anybody know which packet manager uses this format?

# ls
pkg_cfiles
pkg_data
pkg_data32
pkg_data64
pkg_info
pkg_scripts
pkg_signature

# cat pkg_info
PACKAGE=8.2
PKG_TIME=1313434857
PKG_OS=My Unix Operating System
PKG_REVISION=8.2
PKG_VERSION=8.2
PKG_DESCRIPTION=My 8.2 Maintenance
PKG_STATUS=Production
PKG_TYPE=Base
PKG_FLAGS=inactive sysinstall_scripts
REQUIRES=8.1
OBSOLETES=7?*
README=
The 8.2 package provides the following enhancements:

   XXXXXXXXXXX
   XXXXXXXXXXX
   XXXXXXXXXXX

Looks like freebsd, but that is just a guess (due to pkg usage and version numbers i found on google).

Perhaps someone who actually uses that operating system can shed more light.

Regards
Peasant

I tried FreeBSD for the same reason. They are definitely not FreeBSD packages.

The only packages with similar headers available on the Internet looks to be built for the Mcafee Firewall Appliance which runs SecureOS, apparently a customized freeBSD.