diff --git a/htdocs/includes/modules/facture/janus/janus.modules.php b/htdocs/includes/modules/facture/janus/janus.modules.php
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+<?php
+/* Copyright (C) 2005 Rodolphe Quiedeville <rodolphe@quiedeville.org>
+ * Copyright (C) 2005 Éric Seigne <eric.seigne@ryxeo.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * or see http://www.gnu.org/
+ *
+ * $Id$
+ * $Source$
+ *
+ */
+
+/*!	
+  \file       htdocs/includes/modules/facture/janus/janus.modules.php
+  \ingroup    facture
+  \brief      Fichier contenant la classe du modèle de numérotation de référence de facture Janus
+  \version    $Revision$
+*/
+
+
+/*!
+  \class mod_facture_janus
+  \brief      Classe du modèle de numérotation de référence de facture Janus
+*/
+
+class mod_facture_janus extends ModeleNumRefFactures
+{
+
+    /*!     \brief      Renvoi la description du modele de numérotation
+     *      \return     string      Texte descripif
+     */
+    function info()
+    {
+      return "
+    Renvoie le numéro de facture sous une forme spéciale F50201 pour la 1ere facture de février 2005";
+    }
+
+    /*!     \brief      Renvoi un exemple de numérotation
+     *      \return     string      Example
+     */
+    function getExample()
+    {
+        return "F50201";
+    }
+
+    /*!     \brief      Renvoie la référence de facture suivante non utilisée
+     *      \param      objsoc      Objet société
+     *      \return     string      Texte descripif
+     */
+    function getNumRef($objsoc=0)
+    { 
+      global $db;
+      global $fac;
+      
+      $prefix='F';
+      $annee = substr(strftime("%y", $fac->date),-1,1);
+      $mois = strftime("%m", $fac->date);
+      $num=0;
+      
+      $sql = "SELECT max(0+substring(facnumber,8)) FROM ".MAIN_DB_PREFIX."facture";
+      $sql .= " WHERE facnumber like '$prefix".$annee.$mois."%'";
+    
+      if ( $db->query($sql) ) 
+        {
+          $row = $db->fetch_row(0);
+	  
+          $num = $row[0];
+        }
+      $num++;
+      $num=sprintf("%02s",$num);
+      return  "$prefix" . $annee . $mois . $num;
+    }    
+}
+?>