diff --git a/system/language/english/form_validation_lang.php b/system/language/english/form_validation_lang.php
index e22b356..a809f1f 100644
--- a/system/language/english/form_validation_lang.php
+++ b/system/language/english/form_validation_lang.php
@@ -26,32 +26,32 @@
  */
 defined('BASEPATH') OR exit('No direct script access allowed');
 
-$lang['required']				= 'The {field} field is required.';
-$lang['isset']					= 'The {field} field must have a value.';
-$lang['valid_email']			= 'The {field} field must contain a valid email address.';
-$lang['valid_emails']			= 'The {field} field must contain all valid email addresses.';
-$lang['valid_url']				= 'The {field} field must contain a valid URL.';
-$lang['valid_ip']				= 'The {field} field must contain a valid IP.';
-$lang['min_length']				= 'The {field} field must be at least {param} characters in length.';
-$lang['max_length']				= 'The {field} field cannot exceed {param} characters in length.';
-$lang['exact_length']			= 'The {field} field must be exactly {param} characters in length.';
-$lang['alpha']					= 'The {field} field may only contain alphabetical characters.';
-$lang['alpha_numeric']			= 'The {field} field may only contain alpha-numeric characters.';
-$lang['alpha_dash']				= 'The {field} field may only contain alpha-numeric characters, underscores, and dashes.';
-$lang['numeric']				= 'The {field} field must contain only numbers.';
-$lang['is_numeric']				= 'The {field} field must contain only numeric characters.';
-$lang['integer']				= 'The {field} field must contain an integer.';
-$lang['regex_match']			= 'The {field} field is not in the correct format.';
-$lang['matches']				= 'The {field} field does not match the {param} field.';
-$lang['differs']				= 'The {field} field must differ from the {param} field.';
-$lang['is_unique'] 				= 'The {field} field must contain a unique value.';
-$lang['is_natural']				= 'The {field} field must only contain digits.';
-$lang['is_natural_no_zero']		= 'The {field} field must only contain digits and must be greater than zero.';
-$lang['decimal']				= 'The {field} field must contain a decimal number.';
-$lang['less_than']				= 'The {field} field must contain a number less than {param}.';
-$lang['less_than_equal_to']		= 'The {field} field must contain a number less than or equal to {param}.';
-$lang['greater_than']			= 'The {field} field must contain a number greater than {param}.';
-$lang['greater_than_equal_to']	= 'The {field} field must contain a number greater than or equal to {param}.';
+$lang['form_validation_required']		= 'The {field} field is required.';
+$lang['form_validation_isset']			= 'The {field} field must have a value.';
+$lang['form_validation_valid_email']		= 'The {field} field must contain a valid email address.';
+$lang['form_validation_valid_emails']		= 'The {field} field must contain all valid email addresses.';
+$lang['form_validation_valid_url']		= 'The {field} field must contain a valid URL.';
+$lang['form_validation_valid_ip']		= 'The {field} field must contain a valid IP.';
+$lang['form_validation_min_length']		= 'The {field} field must be at least {param} characters in length.';
+$lang['form_validation_max_length']		= 'The {field} field cannot exceed {param} characters in length.';
+$lang['form_validation_exact_length']		= 'The {field} field must be exactly {param} characters in length.';
+$lang['form_validation_alpha']			= 'The {field} field may only contain alphabetical characters.';
+$lang['form_validation_alpha_numeric']		= 'The {field} field may only contain alpha-numeric characters.';
+$lang['form_validation_alpha_dash']		= 'The {field} field may only contain alpha-numeric characters, underscores, and dashes.';
+$lang['form_validation_numeric']		= 'The {field} field must contain only numbers.';
+$lang['form_validation_is_numeric']		= 'The {field} field must contain only numeric characters.';
+$lang['form_validation_integer']		= 'The {field} field must contain an integer.';
+$lang['form_validation_regex_match']		= 'The {field} field is not in the correct format.';
+$lang['form_validation_matches']		= 'The {field} field does not match the {param} field.';
+$lang['form_validation_differs']		= 'The {field} field must differ from the {param} field.';
+$lang['form_validation_is_unique'] 		= 'The {field} field must contain a unique value.';
+$lang['form_validation_is_natural']		= 'The {field} field must only contain digits.';
+$lang['form_validation_is_natural_no_zero']	= 'The {field} field must only contain digits and must be greater than zero.';
+$lang['form_validation_decimal']		= 'The {field} field must contain a decimal number.';
+$lang['form_validation_less_than']		= 'The {field} field must contain a number less than {param}.';
+$lang['form_validation_less_than_equal_to']	= 'The {field} field must contain a number less than or equal to {param}.';
+$lang['form_validation_greater_than']		= 'The {field} field must contain a number greater than {param}.';
+$lang['form_validation_greater_than_equal_to']	= 'The {field} field must contain a number greater than or equal to {param}.';
 
 /* End of file form_validation_lang.php */
 /* Location: ./system/language/english/form_validation_lang.php */
\ No newline at end of file
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index ecd5b18..6853425 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -609,7 +609,9 @@
 				{
 					$line = $this->_error_messages[$type];
 				}
-				elseif (FALSE === ($line = $this->CI->lang->line($type)))
+				elseif (FALSE === ($line = $this->CI->lang->line('form_validation_'.$type))
+					// DEPRECATED support for non-prefixed keys
+					&& FALSE === ($line = $this->CI->lang->line($type, FALSE)))
 				{
 					$line = 'The field was not set';
 				}
@@ -749,7 +751,9 @@
 			{
 				if ( ! isset($this->_error_messages[$rule]))
 				{
-					if (FALSE === ($line = $this->CI->lang->line($rule)))
+					if (FALSE === ($line = $this->CI->lang->line('form_validation_'.$rule))
+						// DEPRECATED support for non-prefixed keys
+						&& FALSE === ($line = $this->CI->lang->line($rule, FALSE)))
 					{
 						$line = 'Unable to access an error message corresponding to your field name.';
 					}
@@ -797,7 +801,9 @@
 		if (sscanf($fieldname, 'lang:%s', $line) === 1)
 		{
 			// Were we able to translate the field name?  If not we use $line
-			if (FALSE === ($fieldname = $this->CI->lang->line($line)))
+			if (FALSE === ($fieldname = $this->CI->lang->line('form_validation_'.$line))
+				// DEPRECATED support for non-prefixed keys
+				&& FALSE === ($fieldname = $this->CI->lang->line($line, FALSE)))
 			{
 				return $line;
 			}
@@ -807,7 +813,7 @@
 	}
 
 	// --------------------------------------------------------------------
-	
+
 	/**
 	 * Build an error message using the field and param.
 	 *