source to inherit

<record id="view_picking_withweight_internal_form" model="ir.ui.view">
            <field name="name">stock.picking_withweight.internal.form.view</field>
            <field name="model">stock.picking</field>
            <field name="inherit_id" ref="stock.view_picking_form"/>
            <field name="arch" type="xml">
                <field name="company_id" position="before">
                    <label for="weight" string="Weight"/>
                    <div>
                        <field name="weight" class="oe_inline"/>
                        <field name="weight_uom_id" nolabel="1" class="oe_inline"/>
                    </div>
                     <field name="weight_net"  groups="base.group_no_one" class="oe_inline"/>
                </field>
            </field>
        </record>

the inherit view

 <record id="view_picking_withweight_internal_form_coma" model="ir.ui.view">
            <field name="name">stock.picking_withweight.internal.form.view_coma</field>
            <field name="model">stock.picking</field>
            <field name="inherit_id" ref="delivery.view_picking_withweight_internal_form/>
            <field name="arch" type="xml">
                <field name="weight_net" position="after">
                  <field name="cin"/>
                  <field name="transp"/>
                  <field name="matricule"/>
                </field>
            </field>
        </record>

Errors:

2013-04-24 09:37:45,422 10421 INFO test0 openerp.modules.loading: module delivery_coma: loading delivery_coma_view.xml
2013-04-24 09:37:45,423 10421 ERROR test0 openerp: Failed to initialize database `test0`.
Traceback (most recent call last):
  File "/home/m3asmi/Documents/7-serv/openerp/cli/server.py", line 98, in preload_registry
    db, registry = openerp.pooler.get_db_and_pool(dbname,update_module=update_module)
  File "/home/m3asmi/Documents/7-serv/openerp/pooler.py", line 33, in get_db_and_pool
    registry = RegistryManager.get(db_name, force_demo, status, update_module)
  File "/home/m3asmi/Documents/7-serv/openerp/modules/registry.py", line 192, in get
    update_module)
  File "/home/m3asmi/Documents/7-serv/openerp/modules/registry.py", line 214, in new
    openerp.modules.load_modules(registry.db, force_demo, status, update_module)
  File "/home/m3asmi/Documents/7-serv/openerp/modules/loading.py", line 343, in load_modules
    processed = load_marked_modules(cr, graph, states_to_load, force, status, report, loaded_modules, update_module)
  File "/home/m3asmi/Documents/7-serv/openerp/modules/loading.py", line 258, in load_marked_modules
    loaded, processed = load_module_graph(cr, graph, progressdict, report=report, skip_modules=loaded_modules, perform_checks=perform_checks)
  File "/home/m3asmi/Documents/7-serv/openerp/modules/loading.py", line 189, in load_module_graph
    load_update_xml(module_name, idref, mode)
  File "/home/m3asmi/Documents/7-serv/openerp/modules/loading.py", line 73, in <lambda>
    load_update_xml = lambda *args: _load_data(cr, *args, kind='update_xml')
  File "/home/m3asmi/Documents/7-serv/openerp/modules/loading.py", line 126, in _load_data
    tools.convert_xml_import(cr, module_name, fp, idref, mode, noupdate, report)
  File "/home/m3asmi/Documents/7-serv/openerp/tools/convert.py", line 941, in convert_xml_import
    doc = etree.parse(xmlfile)
  File "lxml.etree.pyx", line 2957, in lxml.etree.parse (src/lxml/lxml.etree.c:56299)