By Katie Marsal

Published: 10:25 PM EST

Apple has reportedly issued new seeds of Mac OS X Snow Leopard and of Leopard 10.5.8 to developers that, at least in the former case, add functionality that was previously only shown at WWDC.

People familiar with the updates to the two in-development releases say the Snow Leopard seed, 10A394, officially provides just compatibility, reliability and security fixes but appears to give developers access to Expose's integration with the Dock.

As demonstrated by Apple executive Phil Schiller earlier this month, the feature lets users click and hold on an app's Dock icon to show the windows relating to that app in equal-sized, organized tiles. The simple change makes it much easier to find a particular window for a project, for example, without having to invoke a specific Expose shortcut. They can also choose to view a selected window at full size to determine if the content inside is what they want.

It's also said that a new Xcode 3.2 build has been released in tandem with the Snow Leopard build.

Those aware of the new seed for 10.5.8 claim that it's now advanced four builds from its previous state, to 9L20. The company appears to be quickly winding up development as it supposedly hasn't mentioned any remaining known bugs and has fixed just a few prior issues, such as problems with using auto-complete on CalDAV servers in iCal, Image Capture's support for large files, and syncing Address Book with MobileMe.

The Mac maker now seems to be asking developers to focus their testing on low-level components like graphics drivers, power management and storage.

Recently, AppleInsider learned that Apple is giving interim Leopard patches nicknames based on ancient gods and refers to 10.5.8 as Loki, though those in the know say Apple hasn't mentioned the name to developers.