B149/B159 phones need to be set to use the same caller ID method as the IP Office system (System | Telephony | Tones & Music | CLI Type).
To set the caller ID type:
1.Press the 
Menu button.
2.Scroll to SETTINGS and press OK.
3.Scroll to CALLER ID and press OK.
4.Select the method that matches the IP Office system and press OK.
5.To exit the menus, press Menu again. To exit the current menu option, press 
.