diff --git a/Classes/PHPExcel/Reader/HTML.php b/Classes/PHPExcel/Reader/HTML.php
index c07cb3ac..508672ce 100644
--- a/Classes/PHPExcel/Reader/HTML.php
+++ b/Classes/PHPExcel/Reader/HTML.php
@@ -217,7 +217,7 @@ class PHPExcel_Reader_HTML extends PHPExcel_Reader_Abstract implements PHPExcel_
     {
         foreach ($element->childNodes as $child) {
             if ($child instanceof DOMText) {
-                $domText = preg_replace('/\s+/', ' ', trim($child->nodeValue));
+                $domText = preg_replace('/\s+/u', ' ', trim($child->nodeValue));
                 if (is_string($cellContent)) {
                     //	simply append the text if the cell content is a plain text string
                     $cellContent .= $domText;