I downloaded sample Java GSS and Jaas Sample applications from Sun's site. Till recently it was working fine with AD 2003 as KDC. I created two users - One for the server and another for the client and ran server as one of the user account. Client was able to get the service ticket for the server user account and gss context was being established.
But when I moved to AD 2008 same application was not working and I had to specifically map one Service Principal Name(SPN) for the server user account.
I need to check whether attaching SPN is required for AD 2008. What is it is User2User context establishment.