error message in rails

Hi,    I used the below syntax in config/initializers, but i am getting the error message two times, please suggest me the better way to over come it

ActionView::Base.field_error_proc = Proc.new do |html_tag, instance|   if html_tag =~ /<(input|label|textarea|select)/     error_class = 'error'     nodes = Hpricot(html_tag)     nodes.each_child { |node| node[:class] = node.classes.push(error_class).join(' ') unless !node.elem? || node[:type] == 'hidden' || node.classes.include?(error_class) }     nodes.to_html   else     html_tag   end end