By Slash Lane

Published: 10:40 AM EST

A release of the fifth maintenance and security update for Apple's Leopard operating system appears to be approaching a release, with the company reported to have lopped the number components requiring evaluation in half.

Developers claim to have received their pre-weekend build of the upcoming Mac OS X 10.5.5 Update on Thursday evening. The new build, labeled 9F32, arrived just days after a smaller subset of developers were equipped with build 9F30, which similarly followed on the heels of build 9F29 distributed more broadly near the start of the week.

With the latest build, Apple has narrowed its testing field from 24 core system components to just 12, according to people familiar with the software. Among the components still in need of further testing are AirPort, graphics drivers, iCal, iChat, screen sharing, and Time Machine, those people say.

Build 9F32 is also reported to have stemmed a nasty memory glitch that was affecting Time Machine volumes formatted in HFS. A problem using the CUPS printing environment with documents loaded into Apple's Preview application is also said to have been fixed.

While Mac OS X 10.5.5 remains hampered by a single known issue related to email search in the company's Mail application, the narrowed focus list combined with more rapid test releases over the past week has led some developers to believe the Update may only be a week or so away.

Only once in recent memory has the Mac maker shaved a large number of components from the focus areas of an impending Mac OS X update late in its development cycle and then spun around to re-broaden them.

Mac OS X 10.5.5 currently weighs in at around 320 megabytes in its bare bones Delta form, those familiar with the software say.