Index: project_issue.module
===================================================================
--- project_issue.module	(revision 1)
+++ project_issue.module	(working copy)
@@ -1110,8 +1110,14 @@
  */
 function project_issue_set_breadcrumb($node, $project) {
   $extra = array();
-  $extra[] = l($project->title, 'node/'. $project->nid);
-  $extra[] = l(t('Issues'), 'project/issues/'. $project->uri);
+  if ($project) {
+    if ($project->nid) {
+      $extra[] = l($project->title, 'node/'. $project->nid);
+    }
+    if ($project->uri) {
+      $extra[] = l(t('Issues'), 'project/issues/'. $project->uri);
+    }
+  }
   // Add the issue title if we're on a comment reply page.
   if (project_issue_is_comment_reply()) {
     $extra[] = l($node->title, 'node/'. $node->nid);