mrp_bom_sale_eiru/sale_order.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
      <record id="sale_order_form" model="ir.ui.view">
          <field name="name">mrp_sale_bom_eiru.sale.order.form</field>
          <field name="model">sale.order</field>
          <field name="inherit_id" ref="sale.view_order_form"/>
          <field name="arch" type="xml">
              <xpath expr="//field[@name='order_line']//tree//field[@name='name']" position="after">
                  <field name="bom_id" groups="mrp_bom_sale_eiru.sale_mrp_bom_group"/>
              </xpath>
              <xpath expr="//field[@name='order_line']//form//field[@name='name']" position="after">
                  <field name="bom_id" groups="mrp_bom_sale_eiru.sale_mrp_bom_group"/>
              </xpath>
          </field>
      </record>
    </data>
</openerp>