Customize “Protection’ Notifcation Page

I have used the page password facility to protect some of my pages with a password. When you click on one of these pages you get a screen show ‘protected’ and the page name along with a password entry box.

What I want to know is there a way of editing/changing the design/look of this page? Is it a template somewhere is wp-admin? If so were?

Any help would be much appreciated – thanks.