In just under a week since Apple last seeded Mac OS X 10.5.1, another build of the first update to Mac OS X Leopard has reached developers hands for testing.

The latest build labelled 9B16 has “no known issues” in its current state, a note accompanying the seed mentions a fix for a serious bug in which file loss can occur in the Finder when moved between directories.

Developers are asked to focus their testing on Time Machine, Mail, iCal, Back To My Mac, Bonjour, AirPort, gaming graphics, networking and the Finder.