VMD_EI_API and custom fields

Hello experts,

I have a requirement to create Vendors and after investigating for a while, i came to this class: VMD_EI_API

In my tests I've been to create vendors with basic data with no problem, BUT in this client they have lots of custom (Z) fields. I see no way of using this class with these fields.

In a normal BAPI SAP usually provides a table called EXTENSIONS but nothing like this (that i can see) exists iun this class.

Maybe appending the fields to the input structure?

Thanks for reading