Help setting up Mail.app with Exchange 2007!?!?!

Hi,

I was very excited when I found out Snow Leopard was being released with Exchange 2007 compatibility, as I use Exchange 2007 for both my business and personal email - but have had endless problems trying to configure my accounts much to my disappointment.

Can anyone enlighten me or give me some tips? I myself have setup and manage my servers.
Can anyone tell me what the server paths (internal/external) should look like?
I have tried all sorts of combinations for the internal and external servers too, from my internal domain to the server's IP. Nothing works.
Also, my username is usually just my name, but I don't get any connection what so ever unless I put the full email address in the "User Name" field.
What changes need to be made to Exchange 2007 on the server i.e. Service Pack updates etc.??
Any help to resolve this would be greatly appreciated!

Nigel