Akshay, my collegue from the ACE team has written a great post about managing a team across 5 time zones.  Its always a difficult challenge to manage a team of 10 regardless, but spreading them across the world definitely adds many complexity dimensions.  The team I manage is spread between just two timezones, but they are 12.5 hours apart :) 

The key factor, especially for directs that are not at the location where you are mostly, is that you continuously communicate and make sure you are listening for key indicators of potential problems before they crop up and become serious.  Along with that of course, are all of the cultural challenges that can come into play.  Microsoft does a great job in supporting their managers and we have access to a great resource that gives us the breakdown on local customs and attitudes across the world.