Index: sites/all/modules/content_taxonomy/content_taxonomy_autocomplete.module
===================================================================
--- sites/all/modules/content_taxonomy/content_taxonomy_autocomplete.module	(revision 1088)
+++ sites/all/modules/content_taxonomy/content_taxonomy_autocomplete.module	(working copy)
@@ -157,6 +157,9 @@
       $terms[] = taxonomy_get_term($entry[$field_key]);
     }
   }
+  if (!$element['#vids']) {
+    $element['#vids'] = array($element['#vid'] => $element['#vid']);
+  }
   $value = content_taxonomy_autocomplete_merge_tags($terms, $element['#vids']);
   $value = !empty($value) ? $value : NULL;
   return array($field_key => $value);
@@ -219,6 +222,9 @@
   }
   
   $value = $element['#value'];
+  if (!$field['vids']) {
+    $field['vids'] = array($field['vid'] => $field['vid']);
+  }
  
   $extracted_ids = content_taxonomy_autocomplete_tags_get_tids($value, $field['vid'], $field['vids'], content_taxonomy_field_get_parent($field), $field['widget']['extra_parent']);
 
@@ -275,6 +281,9 @@
   $content_type_info = _content_type_info();
   $vid = $content_type_info['fields'][$field_name]['vid'];
   $vids = $content_type_info['fields'][$field_name]['vids'];
+  if (!$vids) {
+    $vids = array($vid => $vid);
+  }
   $tid = content_taxonomy_field_get_parent($content_type_info['fields'][$field_name]);
   
   // If the menu system has splitted the search text because of slashes, glue it back.