diff -urp parser_csv/parser_csv.inc parser_csv2/parser_csv.inc
--- parser_csv/parser_csv.inc	2008-12-01 23:44:50.000000000 +0000
+++ parser_csv2/parser_csv.inc	2009-01-12 12:18:51.000000000 +0000
@@ -122,6 +122,9 @@ function _parser_csv_parse_csv($csv_stri
   if (isset($feed->settings['parsers']['parser_csv']['title_rule'])) {
     $title_rule = explode(',', $feed->settings['parsers']['parser_csv']['title_rule']);
   }
+  if (isset($feed->settings['parsers']['parser_csv']['unique_rule'])) {
+    $unique_rule = $feed->settings['parsers']['parser_csv']['unique_rule'];
+  }
   if (isset($feed->settings['parsers']['parser_csv']['description_rule'])) {
     $description_rule = explode(',', $feed->settings['parsers']['parser_csv']['description_rule']);
   }
@@ -172,7 +175,7 @@ function _parser_csv_parse_csv($csv_stri
         $item->description = count($description) ? implode(', ', $description) : '';
         $item->options = new stdClass();
         $item->options->timestamp = $timestamp;
-        $item->options->guid = hash('md5', $line);
+        $item->options->guid = isset($fields[$unique_rule]) ? $fields[$unique_rule] :  hash('md5', $line);
         $item->options->raw = $fields;
 
         // Attach it to feed.
diff -urp parser_csv/parser_csv.module parser_csv2/parser_csv.module
--- parser_csv/parser_csv.module	2008-12-01 23:44:50.000000000 +0000
+++ parser_csv2/parser_csv.module	2009-01-12 12:04:25.000000000 +0000
@@ -65,6 +65,12 @@ function parser_csv_feedapi_settings_for
         '#default_value' => '',
         '#description' => t('Enter a string in the format FIELDNAME1,FIELDNAME2,FIELDNAME3'),
       );
+      $form['unique_rule'] = array(
+        '#type' => 'textfield',
+        '#title' => t('Rule for defining the unique field'),
+        '#default_value' => '',
+        '#description' => t('Enter a string in the format FIELDNAME'),
+      );
       $form['description_rule'] = array(
         '#type' => 'textfield',
         '#title' => t('Rule for building the description field'),