crm_mensaje/res_partner_view.xml

<?xml version="1.0" encoding="UTF-8"?>
<openerp>
    <data>

		 <record id="crm_case_categ_mensaje1" model="ir.actions.act_window">
            <field name="name">Mensajes</field>
            <field name="res_model">crm.mensaje</field>
            <field name="view_type">form</field>
            <field name="view_mode">tree,form</field>
            <field name="context">{'search_default_partner_id': active_id}</field>
            <field name="help" type="html">
              <p class="oe_view_nocontent_create">
                Click to create a quotation or sales order for this customer.
              </p><p>
                Odoo will help you efficiently handle the complete sale flow:
                quotation, sales order, delivery, invoicing and
                payment.
              </p><p>
                The social feature helps you organize discussions on each sales
                order, and allow your customer to keep track of the evolution
                of the sales order.
              </p>
            </field>
        </record>

		<!--  Partners inherited form -->
        <record id="view_mensaje_partner_info_form" model="ir.ui.view">
            <field name="name">res.partner.mensaje.buttons</field>
            <field name="model">res.partner</field>
            <field name="inherit_id" ref="base.view_partner_form"/>
            <field name="priority" eval="50"/>
            <field name="arch" type="xml">
                <xpath expr="//div[@name='buttons']" position="inside">
                    <button class="oe_inline oe_stat_button" type="action" name="%(crm_mensaje.crm_case_categ_mensaje1)d"
						             attrs="{'invisible': [('customer', '=', False)]}"
						             context="{'search_default_partner_id': active_id, 'default_partner_id': active_id}"
						             icon="fa-pencil-square-o">
						             <field  string="Mensajes" name="mensaje_count" widget="statinfo"/>
                    </button>
                </xpath>
            </field>
       </record>

    </data>
</openerp>