function submitForm(form)    
{
  $(form).ajaxSubmit({ 
    target:        '#ajax_form_holder',
    beforeSubmit:  showLoader
  }); 
  return false;
}   

function showLoader()
{
  $('#ajax_loader').css('height', $('#ajax_form_holder').height());
  $('#ajax_loader').css('width', $('#ajax_form_holder').width());
  $('#ajax_loader').show();
}