Apple is working on a huge update for Mac OS X 10.5 Leopard, offering a huge selection of patches to the applications included within the system, a report explains.

Apple has quietly begun testing a OS X 10.5.2, with pre-release builds now in circulation among developers, the report explains. And there's patches for multiple system components, including AirPort, Back To My Mac, Automator, the OS X Firewall, Dashboard, Dock, Finder, graphics drivers, iCal, iChat, iDisk, Safari, Mail, Spotlight, and Time Machine.

In total, the report claims over 40 applications have been vetted with over 100 bugs so far addressed - but Mac users had better ensure they aren't hovering near any bandwidth caps on the part of their ISP - this update currently weighs in at over 400MB, MacScoop claims.