Looking for a good internal phone book software

Looking for a good internal phone book software that would read extension, mobiles, titles and department from Active Directory. We are running Ms Active Directory 2003

There is something called Corporate Directory. It is an address book software that automatically detects you MS domain and reads all contact information from it. It is a client application that runs as a tray icon. The best thing about it is that it uses a "google like" search box. You find results as soon as you start typing a person's name or any other property like title, department etc... The company name is View2C. Let me know if this is what you are looking for.