--- content_taxonomy.module	Thu May 14 16:03:12 2009
+++ content_taxonomy.module	Mon Aug 03 21:50:59 2009
@@ -171,6 +171,10 @@
                 $node->taxonomy[$field['vid']][] = $entry['value'];
               }
             }
+            elseif(is_array($node->taxonomy) && in_array($entry['value'],$node->taxonomy)) {
+            	continue;
+            }
+
             // when saving an existing node without presenting a form to the user,
             // the terms are objects keyed by tid. there's no need to re-set these
             // terms, and to do so causes php warnings because the database rejects
@@ -491,7 +495,7 @@
     return;
   }
   foreach ($form as $key => $value) {
-    if ($key == 'tags') {
+    if ($key === 'tags') {
       _content_taxonomy_taxonomy_unset($form[$key], $vids);
     }
     elseif (is_object($value) && in_array($value->vid, $vids)) {