Index: jquery.drilldown.js
--- jquery.drilldown.js Base (BASE)
+++ jquery.drilldown.js Locally Modified (Based On LOCAL)
@@ -81,7 +81,7 @@
           var trail = $(settings.trail);
           trail.empty();
           for (var key in breadcrumb) {
-            if (breadcrumb[key]) {
+            if (breadcrumb.hasOwnProperty(key)) {
               // We don't use the $().clone() method here because of an
               // IE & jQuery 1.2 bug.
               var clone = $('<a></a>')