Creating Custom Models

The WebDynpro projects supports a few standard ways of implementing the Models

namely RFC, Web Services, XMI.

Can someone tell me as to how can i create a custom model based on my own schema to support a different data source for eg. an LDAP Data etc.

Also how do i implement the backend calls . (like for RFC and WebServices based Models, there is an .execute method on the modelObject). How do i implement this kind of an execute mechanism. is there a standard interface ?

.V