--- context.core.inc	2010-04-29 19:54:34.000000000 +0300
+++ context.core.inc-patched	2010-07-27 17:35:05.273671714 +0300
@@ -349,7 +349,7 @@ function context_node_condition(&$node, 
   }
 
   // Implementation of context for taxonomy.
-  if (module_exists('taxonomy') && $node->taxonomy) {
+  if (module_exists('taxonomy') && isset($node->taxonomy)) {
     // Set context for terms
     foreach ($node->taxonomy as $term) {
       context_set_by_condition('taxonomy', $term->vid .':'. $term->tid);