diff --git a/tests/Zend/Validate/HostnameTest.php b/tests/Zend/Validate/HostnameTest.php
index fcd73fb69f..41d82fb655 100644
--- a/tests/Zend/Validate/HostnameTest.php
+++ b/tests/Zend/Validate/HostnameTest.php
@@ -518,4 +518,13 @@ public function testRussianIdn()
         $this->assertTrue($validator->isValid('кц.рф'));
         $this->assertTrue($validator->isValid('президент.рф'));
     }
+
+    /**
+     * @group GH-451
+     */
+    public function testVermögensberaterIdns()
+    {
+        $validator = new Zend_Validate_Hostname();
+        $this->assertTrue($validator->isValid('mysite.vermögensberater'));
+    }
 }