How to provide default values in dropdown in employee interaction center?how to add dropdown values in EIC role?where we write the code?

Hi

Iam a new of SAP CRM EIC,can u please tell me how to provide drop downl list values in sap crm EIC.my requirement is ,

"From" field in all out going calls should be dafuletd to " AskHRfront office" maill box of the my hr team.

Next one how to remove drop down values in Email address tab//because here there is no geter methods and where we need to write the logic?and here there is no contet nodes and attributes in EIC screen..

please provide me the information!!!

Thanks@

Kalpana