Hello richfaces forum

I would like to use a combobox with a valuelist and a displaylist. Actually the combobox is able to work with selectItems. SelectItems do provide the properties
- value
- label
- description.
I would like to provide contacts in the combobox. A contact has
- a contactId (integer)
- a firstName and lastName
I want to display the firstName and lastName as the label. And the integer contactId as the value (not visible to the user).

This is for example working properly in the richfaces pickList. I am wondering why the comboBox is not supporting this feature?

Do you have an idea how I could realise that requirement?. Thank you for a reply.