articles_callback: do not try to extract counters when transport.responseXML is MIA

viewfeed.js

@@ -362,6 +362,7 @@ function article_callback2(transport, id, feed_id) {
 			setTimeout('updateFeedList(false, false)', 50);			
 			_reload_feedlist_after_view = false;
 		} else {
+			if (transport.responseXML) {
 				var counters = transport.responseXML.getElementsByTagName("counters")[0];
 
 				if (counters) {
@@ -372,6 +373,7 @@ function article_callback2(transport, id, feed_id) {
 					request_counters();
 				}
 			}
+		}
 
 		notify("");
 	} catch (e) {