diff --git a/lib/DAV/Xml/Element/Response.php b/lib/DAV/Xml/Element/Response.php
index 45c161fa4f..434d27d401 100644
--- a/lib/DAV/Xml/Element/Response.php
+++ b/lib/DAV/Xml/Element/Response.php
@@ -121,7 +121,7 @@ public function xmlSerialize(Writer $writer)
 
         foreach ($this->getResponseProperties() as $status => $properties) {
             // Skipping empty lists
-            if (!$properties || (!ctype_digit($status) && !is_int($status))) {
+            if (!$properties || (!is_int($status) && !ctype_digit($status))) {
                 continue;
             }
             $empty = false;