Uncaught Error in search view account.analytic.account

Hi!
i have altered the account.analytic.account to this:
class account_analytic_account(osv.osv):
    _inherit='account.analytic.account'
    _columns = {
         'tipo_dim':fields.selection([('uo', u'Orgânica'), ('ce', u'Económica'),
                                    ('cf', u'Funcional'), ('cc', u'Centro de Custo')],
                                     u'Dimensão', required=True, select=2,
                                 ),
         'parent_id':fields.many2one('account.analytic.account',"Parent Analytic Account", domain="[('tipo_dim','=',tipo_dim),('type','=','view')]"),
         'code':fields.char("Reference",required=True),
         }
 i have defined a tree view:
<record model="ir.ui.view" id="account_multidim_tree">
            <field name="name">account.analytic.multidim.tree</field>
            <field name="model">account.analytic.account</field>
            <field name="inherit_id" ref="account.view_account_analytic_account_tree"/>
            <field name="arch" type="xml">
                <data>
                    <field name='complete_name' position="before">
                        <field name="tipo_dim" groups="account.group_account_user"/>
                    </field>
                    <field name="parent_id" position="replace">
                        <field name="parent_id"/>
                    </field>
                    <field name="code" position="replace">
                        <field name="code"/>
                    </field>
                </data>
            </field>
          </record>

and form view:

<record model="ir.ui.view" id="account_multidim_form">
            <field name="name">account.analytic.multidim</field>
            <field name="model">account.analytic.account</field>
            <field name="inherit_id" ref="analytic.view_account_analytic_account_form"/>
            <field name="arch" type="xml">
                <data>
                    <field name='name' position="after">

                        <h4><label string="Tipo de Dimensão" attrs="{'invisible':[('tipo_dim','in',['cc','ce','uo','cf'])]}"/></h4>
                        <field name="tipo_dim" attrs="{'invisible':[('tipo_dim','in',['cc','ce','uo','cf'])]}"
                                groups="account.group_account_user"/>

                        <separator colspan="4"/>
                    </field>
                    <field name="parent_id" position="replace">
                        <field name="parent_id"/>
                    </field>
                    <field name="code" position="replace">
                        <field name="code"/>
                    </field>

                </data>
            </field>
        </record>

and search view:
<record model="ir.ui.view" id="account_multidim_search">
            <field name="name">account.analytic.multidim.search</field>
            <field name="model">account.analytic.account</field>
            <field name="arch" type="xml">
                <search string="Analytic Account">
                    <field name="name" filter_domain="['|', ('name','ilike',self), ('code','ilike',self)]" string="Analytic Account"/>
                    <field name="date"/>
                    <field name="tipo_dim" domain="[]"/>
                    <field name="partner_id" filter_domain="[('partner_id','child_of',self)]"/>
                    <field name="manager_id"/>
                    <field name="parent_id"/>
                    <field name="user_id"/>
                    <filter string="Orgánica" domain="[('tipo_dim','=','uo')]" help="CCC"/>
                    <filter string="Económica" domain="[('tipo_dim','=','ce')]" help="CCC"/>
                    <filter string="Funcional" domain="[('tipo_dim','=','cf')]" help="CCC"/>
                    <filter string="Open" domain="[('state','=','open')]" help="Current Accounts"/>
                    <filter string="Pending" domain="[('state','=','pending')]" help="Pending Accounts"/>
                    <group expand="0" string="Group By...">
                        <filter string="BBB" domain="[]" context="{'group_by':'type'}"/>
                        <filter string="Associated Partner" domain="[]" context="{'group_by':'partner_id'}"/>
                        <filter string="Type" domain="[]" context="{'group_by':'type'}"/>
                        <filter string="Template" domain="[]" context="{'group_by':'template_id'}"/>
                        <filter string="Parent Account" domain="[]" context="{'group_by':'parent_id'}"/>
                        <filter string="Status" domain="[]" context="{'group_by':'state'}" groups="base.group_no_one"/>
                    </group>
                </search>
            </field>
            </record>

all the filters work fine, but when i try to type smth in the search field the next client error appears:

Uncaught Error: NameError: name 'tipo_dim' is not defined

Whar did i missed???