Passing information from an iView to SAP - ESS Related

Hi,

How do you pass information from an iView to SAP?

For example, in my task the User will log into ESS.

Then they will click on the iView link and be prompted with a dialog for their service number (how is that done)?

Now, on SAP's side (backend), I need to take that service number and their user id and pass it to the transaction.

For the service number, I will have to add leading zero's.

How is this done?

What is the ESS cookbook and does anyone have it?

Thanks,

John