--- modules/node.module.orig	2004-06-07 18:44:39.000000000 -0400
+++ modules/node.module	2004-06-10 20:48:56.170688942 -0400
@@ -92,12 +92,12 @@ function node_tag_new($nid) {
   global $user;
 
   if ($user->uid) {
-    $result = db_query('SELECT timestamp FROM {history} WHERE uid = %d AND nid = %d', $user->uid, $nid);
-    if (db_fetch_object($result)) {
-      db_query('UPDATE {history} SET timestamp = %d WHERE uid = %d AND nid = %d', time(), $user->uid, $nid);
-    }
-    else {
-      db_query('INSERT INTO {history} (uid, nid, timestamp) VALUES (%d, %d, %d)', $user->uid, $nid, time());
+    db_query('UPDATE {history} SET timestamp = %d WHERE uid = %d AND nid = %d', time(), $user->uid, $nid);
+    if (!db_affected_rows()) {
+      if ($key = lock_lock($user->uid.$nid)) {
+        db_query('INSERT INTO {history} (uid, nid, timestamp) VALUES (%d, %d, %d)', $user->uid, $nid, time());
+        lock_unlock($user->uid.$nid, $key);
+      }
     }
   }
 }