mrp_bom_sale_eiru/sale_order_line.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <record id="sale_order_line_tree" model="ir.ui.view">
            <field name="name">mrp_sale_bom.sale.order.line.tree</field>
            <field name="model">sale.order.line</field>
            <field name="inherit_id" ref="sale.view_order_line_tree"/>
            <field name="arch" type="xml">
                <field name="name" position="after">
                    <field name="bom_id" groups="mrp_bom_sale_eiru.sale_mrp_bom_group"/>
                </field>
            </field>
         </record>
      </data>
  </openerp>