global address list

Hello,

I have gone around and around on the microsoft forums with this and i still have yet to find a solution. I need to create an address book for my small business that can be accessed via desktop and mobile applications. I am using the following:

iphone 4

Windows 7 with outlook 2010

windows xp with outlook 2007

exchange 365

Now, i can create a shared contactlist and share it with others and see it just fine on their outlook. However, when i try and view shared contact lists on iphone it shows nothing. Several people mentioned that the iphone can't process shared calendars or contact lists. So, i tried to look at using the global address list. It shows up on all my iphones but it only searches contacts inside the organization. Does anyone out there know of a simplistic way to create a shared contact list on my mobile devices? Is it something i need to setup with my global address list???