function unserialize($str)
 {
     global $include_path;
     global $openurl_map;
     global $url_ctx_val, $url_ctx_ref;
     $openurl_map = array();
     //on va avoir besoin du mapping...
     require_once "{$include_path}/parser.inc.php";
     _parser_($include_path . "/openurl/openurl_mapping.xml", array("ITEM" => "_getMapItem_"), "MAP");
     $ctx = new openurl_context_object_kev_mtx_ctx();
     if ($url_ctx_val != "") {
         //Transport By-Value
         $ctx->unserialize($url_ctx_val);
     } else {
         if ($url_ctx_ref != "") {
             //Transport By-Reference
             $content = openurl_transport_http::get($url_ctx_ref);
             $ctx->unserialize($content);
         } else {
             //Transport Inline
             $ctx->unserialize($str);
         }
     }
 }