Merge upstream branch
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index 8a5d8ea..8a27935 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -2,7 +2,7 @@
 /**
  * CodeIgniter
  *
- * An open source application development framework for PHP 5.1.6 or newer
+ * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
  *
@@ -51,6 +51,18 @@
 	{
 		$this->CI =& get_instance();
 
+		// applies delimiters set in config file.
+		if (isset($rules['error_prefix']))
+		{
+			$this->_error_prefix = $rules['error_prefix'];
+			unset($rules['error_prefix']);
+		}
+		if (isset($rules['error_suffix']))
+		{
+			$this->_error_suffix = $rules['error_suffix'];
+			unset($rules['error_suffix']);
+		}
+
 		// Validation rules can be stored in a config file.
 		$this->_config_rules = $rules;
 
@@ -58,7 +70,7 @@
 		$this->CI->load->helper('form');
 
 		// Set the character encoding in MB.
-		if (function_exists('mb_internal_encoding'))
+		if (MB_ENABLED === TRUE)
 		{
 			mb_internal_encoding($this->CI->config->item('charset'));
 		}
@@ -87,7 +99,7 @@
 			return $this;
 		}
 
-		// If an array was passed via the first parameter instead of indidual string
+		// If an array was passed via the first parameter instead of individual string
 		// values we cycle through it and recursively call this function.
 		if (is_array($field))
 		{
@@ -925,7 +937,7 @@
 			return FALSE;
 		}
 
-		if (function_exists('mb_strlen'))
+		if (MB_ENABLED === TRUE)
 		{
 			return ! (mb_strlen($str) < $val);
 		}
@@ -949,7 +961,7 @@
 			return FALSE;
 		}
 
-		if (function_exists('mb_strlen'))
+		if (MB_ENABLED === TRUE)
 		{
 			return ! (mb_strlen($str) > $val);
 		}
@@ -973,7 +985,7 @@
 			return FALSE;
 		}
 
-		if (function_exists('mb_strlen'))
+		if (MB_ENABLED === TRUE)
 		{
 			return (mb_strlen($str) == $val);
 		}
@@ -1337,4 +1349,4 @@
 }
 
 /* End of file Form_validation.php */
-/* Location: ./system/libraries/Form_validation.php */
+/* Location: ./system/libraries/Form_validation.php */
\ No newline at end of file