Fixed an empty string error
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index fd0c22e..b658011 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -319,7 +319,7 @@
 			}

 			else

 			{

-				if (isset($_POST[$field]))

+				if (isset($_POST[$field]) AND $_POST[$field] != "")

 				{

 					$this->_field_data[$field]['postdata'] = $_POST[$field];

 				}