by , 9:15 AM EST, November 19th, 2007

The Open Group announced on Monday that Mac OS X 10.5 and Mac OS X 10.5 Server have been certified as in conformance with the UNIX 03 standard. The certification is considered a milestone because Mac OS X is the first BSD-based operating system to meet the certification requirements.

The Open Group, which touts itself as a "vendor- and technology-neutral consortium focused on open standards and global interoperability within and between enterprises," stated that the certification means Leopard complies with the Unix latest product standard as developed by The Open Group Platform Forum. It also means that Leopard includes a set of standard interfaces that lets developers port standards-compliant applications between Unix variants.

Additional UNIX 03-compliant products are available from IBM, Sun Microsystems, Fujitsu, Hewlett-Packard, and more.