How to display extension on phone display constantly?

[sk1053]

I'm using PSA and for this reason I can label the call-appr buttons with the extensions as they roam with the people using them. I would like the phone ext to be displayed permanently in the phone next to the date/time so they dont have any confusion as to which extension they are using.
I can see in sys features where the date/time are set but nothing to display the ext. Is it possible? Using Definity V9. Cheers

 

[sk1053]

forgot to mention that the phone is a 6416D+

 

[velcrobomb]

The only thing I think you can do is assign btn-view to one of the feature buttons. Then view the call-appearance buttons with that. It won't remain permanant though.