Crm 2013: Xrm.Page.ui.getFormType() throws error on customeraddress

Hi,

I am trying to work with Xrm.Page.ui.getFormType() on customeraddress form and it throws an error saying Xrm.Page.ui is null. Why the ui object is null in customeraddress form? All other inline forms are showing correct values using the same line of JavaScript.

I am using Crm 2013.

Ahmad