title: How to add custom attribute to customer export csv
body: <p>I have 4 custom attrubute for customer.i would like to add it in csv when export.i have add it in grid for export only but it seem not working.csv created but data not fill in the csv.
  below is code to use for csv import in grid.php.</p>
  
  <pre><code>       if ($this-&gt;_isExport) { 
       $this-&gt;addColumn('contact_job_title', array(
      'header' =&gt; Mage::helper('customer')-&gt;__('Contact Job Title'),
      'index'  =&gt; 'contact_job_title',
  ));
   $this-&gt;addColumn('contact_seq_no', array(
      'header' =&gt; Mage::helper('customer')-&gt;__('Contact Seq No'),
      'index'  =&gt; 'contact_seq_no',
  ));
  $this-&gt;addColumn('debtor_acc_no', array(
      'header' =&gt; Mage::helper('customer')-&gt;__('Debtor Acc No'),
      'index'  =&gt; 'debtor_acc_no',
  ));
  $this-&gt;addColumn('debtor_api_key', array(
      'header' =&gt; Mage::helper('customer')-&gt;__('Debtor Api Key'),
      'index'  =&gt; 'debtor_api_key',
  ));
      }
  </code></pre>
  
  <p>any help would be appreciate.</p>