Apple released another important update to its Leopard operating system for Mac computers. The software update fixes more than 21 security weakness for the Mac.

The update bundle is available for free download via Software Update or Apple Downloads.

Security Update 2008-008 for Mac OS X 10.4.11 users includes many of the security updates found in Mac OS X 10.5.6. released on Monday. Seven of the updates included in the bundle fix problems for the Mac version of Adobe Flash player. The flaws were patched last month by Adobe.

The bundle update completes or corrects problems linked to certain file downloads, CoreGraphics, CoreServices, Adobe's Flash Player plug-in, Libsystem, Internet Sharing, and opening ISO files.

The security bundle update offers "general operating system fixes that enhance the stability, compatibility, and security of your Mac," as Apple said. In a note on its Web site, the Cupertino, California-based company advised its users to proceed cautiously with the update pack warning them of the unexpected results they may get if they have third-party software modifications installed on their Mac. Users of the update could also encounter problems if they have moved applications from their default locations.

For example, gamers who download and install the update will notice that it improves performance of several games and also fixes image distortions that are usually encountered at some ATI graphics cards. Good news for Mobile Me users as well: the update makes syncing faster for contacts, calendars, and bookmark lists.

The update is also designed to boost performance and fix flaws in Apple's Time Machine archiving system, Safari Web browser, DVD player, and TrackPad portable input system.

Here’s a full list of issues which the security update is designed to fix.