Constrained delegation for EFS sharing

Hi

In Windwos 2003 server (in a 2003 domain) with a shared EFS folder to allow 5 XP clients to encrypt and decrypt files on the Windows 2003 server shared folder.

Right click on the server computer object properties, on the Delegation tab, on the "Trust this computer for delegation to specified services only" - What are the servcies required for remote EFS sharing to work?

Thank you.