diff --git a/src/SchillingSoapWrapper.php b/src/SchillingSoapWrapper.php
index <HASH>..<HASH> 100644
--- a/src/SchillingSoapWrapper.php
+++ b/src/SchillingSoapWrapper.php
@@ -108,7 +108,7 @@ class SchillingSoapWrapper
     {
         $dom = new DOMDocument();
         $dom->formatOutput = true;
-        $dom->preserveWhitespace = false;
+        $dom->preserveWhiteSpace = false;
         $dom->loadXml($xml);
 
         return $dom->saveXml();
Fixed caps in DOM preserveWhiteSpace