diff --git a/Classes/PHPExcel/Calculation.php b/Classes/PHPExcel/Calculation.php
index 1ec49c40..b3931dc7 100644
--- a/Classes/PHPExcel/Calculation.php
+++ b/Classes/PHPExcel/Calculation.php
@@ -2613,7 +2613,7 @@ class PHPExcel_Calculation {
 							   '|'.self::CALCULATION_REGEXP_CELLREF.
 							   '|'.self::CALCULATION_REGEXP_NAMEDRANGE.
 							   '|'.self::CALCULATION_REGEXP_ERROR.
-							 ')/siU';
+							 ')/si';
 
 		//	Start with initialisation
 		$index = 0;