diff --git a/plugins/libkolab/lib/kolab_storage_config.php b/plugins/libkolab/lib/kolab_storage_config.php
index b29e7a90..ee316145 100644
--- a/plugins/libkolab/lib/kolab_storage_config.php
+++ b/plugins/libkolab/lib/kolab_storage_config.php
@@ -236,7 +236,7 @@ class kolab_storage_config
         // on success, update cached tags list
         if ($status && is_array($this->tags)) {
             foreach ($this->tags as $idx => $tag) {
-                if ($tag['uid'] == $uid) {
+                if ($tag['uid'] == $object['uid']) {
                     unset($this->tags[$idx]);
                     break;
                 }
diff --git a/plugins/libkolab/tests/kolab_storage_config.php b/plugins/libkolab/tests/kolab_storage_config.php
index 9be7841f..50a894f2 100644
--- a/plugins/libkolab/tests/kolab_storage_config.php
+++ b/plugins/libkolab/tests/kolab_storage_config.php
@@ -230,5 +230,9 @@ class kolab_storage_config_test extends PHPUnit_Framework_TestCase
         // get tags again, make sure it contains the new tag
         $tags = $config->get_tags();
         $this->assertCount(4, $tags);
+
+        foreach ($tags as $_tag) {
+            $this->assertTrue($_tag['uid'] != $tag['uid']);
+        }
     }
 }