Index: user.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/user.module,v
retrieving revision 1.496
diff -u -r1.496 user.module
--- user.module	1 Aug 2005 05:14:05 -0000	1.496
+++ user.module	3 Aug 2005 10:26:30 -0000
@@ -1634,12 +1634,18 @@
   $id = arg(4);
 
   if ($op == t('Save role')) {
-    if ($edit['name']) {
+    $rid = db_result(db_query("SELECT rid FROM {role} WHERE name = '%s'", $edit['name']));
+    if ($rid) {
+      form_set_error('name', t('You must specify a unique role name.'));
+      drupal_goto("admin/access/roles/edit/$id");
+    }
+    else if ($edit['name']) {
       db_query("UPDATE {role} SET name = '%s' WHERE rid = %d", $edit['name'], $id);
       drupal_set_message(t('The changes have been saved.'));
     }
     else {
       form_set_error('name', t('You must specify a valid role name.'));
+      drupal_goto("admin/access/roles/edit/$id");
     }
   }
   else if ($op == t('Delete role')) {
@@ -1665,7 +1671,12 @@
     drupal_goto('admin/access/roles');
   }
   else if ($op == t('Add role')) {
-    if ($edit['name']) {
+    $result = db_query("SELECT rid FROM {role} WHERE name = '%s'", $edit['name']);
+    $role = db_fetch_object($result);
+    if (isset($role->rid)) {
+      form_set_error('name', t('You must specify a unique role name.'));
+    }
+    else if ($edit['name']) {
       db_query("INSERT INTO {role} (name) VALUES ('%s')", $edit['name']);
       drupal_set_message(t('The role has been added.'));
       drupal_goto('admin/access/roles');