diff --git a/Classes/PHPExcel/Calculation/Functions.php b/Classes/PHPExcel/Calculation/Functions.php
index 3e6a56db..5de66c41 100644
--- a/Classes/PHPExcel/Calculation/Functions.php
+++ b/Classes/PHPExcel/Calculation/Functions.php
@@ -308,6 +308,8 @@ class PHPExcel_Calculation_Functions {
 
 	public static function _ifCondition($condition) {
 		$condition	= PHPExcel_Calculation_Functions::flattenSingleValue($condition);
+		if (!isset($condition{0}))
+			$condition = '=""';
 		if (!in_array($condition{0},array('>', '<', '='))) {
 			if (!is_numeric($condition)) { $condition = PHPExcel_Calculation::_wrapResult(strtoupper($condition)); }
 			return '='.$condition;