manufacture/mrp_production_properties/mrp_view.xml

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

        <record id="mrp_production_form_view" model="ir.ui.view">
            <field name="name">mrp.production.form</field>
            <field name="model">mrp.production</field>
            <field name="inherit_id" ref="mrp.mrp_production_form_view"/>
            <field name="arch" type="xml">
                <xpath expr="//field[@name='priority']" position="after">
                        <field name="property_ids" widget="many2many_tags"/>
                </xpath>
            </field>
        </record>

    </data>
</openerp>