--- unique_field.module.orig	2009-03-31 10:30:11.000000000 +1000
+++ unique_field.module	2009-03-31 13:36:28.000000000 +1000
@@ -29,6 +29,7 @@ define('UNIQUE_FIELD_COMP_ALL', 'all');
 // query field definitions
 define('UNIQUE_FIELD_FIELDS_TITLE', 'title');
 define('UNIQUE_FIELD_FIELDS_AUTHOR', 'name');
+define('UNIQUE_FIELD_FIELDS_TAXONOMY', 'taxonomy_');
 
 // setting definition
 define('UNIQUE_FIELD_SHOW_MATCHES', 'show_matches');
@@ -127,6 +128,15 @@ function unique_field_nodeapi(&$node, $o
           else if ($field == UNIQUE_FIELD_FIELDS_AUTHOR) {
             $values = $node->uid;
           }
+          elseif (strpos($field, UNIQUE_FIELD_FIELDS_TAXONOMY) === 0) {
+            $vid = str_replace(UNIQUE_FIELD_FIELDS_TAXONOMY, '', $field);
+            $values = array();
+            foreach ($node->taxonomy as $vocabulary => $terms) {  
+              if ($vocabulary == $vid) {
+                $values = array_merge($values, $terms);
+              }
+            }
+          }
           else {
             // if cck_field_perms is enabled and the current user is
             // not permitted to access a field, then the field data is cleared
@@ -175,6 +185,11 @@ function unique_field_nodeapi(&$node, $o
           else if ($field == UNIQUE_FIELD_FIELDS_AUTHOR) {
             $labels[$field] = t('Author');
           }
+          elseif (strpos($field, UNIQUE_FIELD_FIELDS_TAXONOMY) === 0) {
+            $vid = str_replace(UNIQUE_FIELD_FIELDS_TAXONOMY, '', $field);
+            $vocabulary = taxonomy_get_vocabulary($vid);
+            $labels[$field] = $vocabulary->name;
+          }
           else {
             $fld = content_fields($field, $node->type);
             $labels[$field] = $fld['widget']['label'];
@@ -208,6 +223,7 @@ function unique_field_match_value($field
   // initialize query variables
   $qtbl = '';
   $qwhere = '';
+  $qjoinfield = 'vid'; // Only needed for D5
 
   // generate query where clause for title field
   if ($field === UNIQUE_FIELD_FIELDS_TITLE) {
@@ -218,6 +234,13 @@ function unique_field_match_value($field
   else if ($field === UNIQUE_FIELD_FIELDS_AUTHOR) {
     $qwhere = "node.uid = '". intval($values) ."' ";
   }
+  
+  // generate query where clause for taxonomy term
+  elseif (strpos($field, UNIQUE_FIELD_FIELDS_TAXONOMY) === 0) {
+    $qtbl = 'term_node';
+    $qjoinfield = 'nid'; // Only needed for D5
+    $qwhere = "term_node.tid = '". implode("' OR term_node.tid = '", $values) ."' ";
+  }
 
   // generate query where clause for a CCK field
   else {
@@ -282,7 +305,7 @@ function unique_field_match_value($field
   // do query
   $q = "SELECT node.nid FROM {node} node ";
   if (!empty($qtbl)) {
-    $q .= "JOIN {". $qtbl ."} AS ". $qtbl ." USING (vid) ";
+    $q .= "JOIN {". $qtbl ."} AS ". $qtbl ." USING (". $qjoinfield .") ";
   }
   $q .= "WHERE ". $qwhere;
   $res = db_query($q);
@@ -313,6 +336,14 @@ function unique_field_node_settings_form
       }
     }
   }
+  if (module_exists('taxonomy')) {
+    $vocabularies = taxonomy_get_vocabularies($ntype);
+    if (is_array($vocabularies)) {
+      foreach ($vocabularies as $vocabulary) {
+        $fieldopts[UNIQUE_FIELD_FIELDS_TAXONOMY . $vocabulary->vid] = 'Taxonomy: Terms for '. $vocabulary->name;
+      }
+    }
+  }
 
   // build the form
   $form['unique_field'] = array(