I'm trying to customize the res.partner view in Odoo 8, what I want Is to be able to change the placeholder or the string of some fields that are shown on the form through attributes, but no luck so far.

I have this code:

<xpath expr="//field[@name='mobile']" position="attributes">

<attribute name="attrs">{'placeholder':"Cellphone Numer", 'required':True}</attribute>

</xpath>

The required works just fine and the field appears in blue, but no placeholder text.