EHP4 for SAP Netweaver 2004

Hi All,

As of now our system has EHP3 implemented but we want to go for EHP4. So for EHP4, I want to know Differences as compared to EHP3 for the following

1) HCM forms and Scenarios

2) SAP E-Recruiting

3) Employee Interaction center (EIC)

4) Performance management system (Especially user interface for Performance development review form; for EHP3 it uses BSP. Like to know whether for EHP4 it uses BSP or Web Dynpro)

Cheers,

Abhishek Jain