diff --git a/forms/CreditCardField.php b/forms/CreditCardField.php
index <HASH>..<HASH> 100755
--- a/forms/CreditCardField.php
+++ b/forms/CreditCardField.php
@@ -73,6 +73,9 @@ JS;
 	}
 	
 	function validate($validator){
+		// If the field is empty then don't return an invalidation message
+		if(!trim(implode("", $this->value))) return true;
+		
 		$i=0;
 		if($this->value) foreach($this->value as $part){
 			if(!$part || !(strlen($part) == 4) || !ereg("([0-9]{4})",$part)){
If the credit card field is completely blank, then it's not invalid.  Required-fields should be used to check for values

git-svn-id: svn://svn.silverstripe.com/silverstripe/open/modules/sapphire/trunk@<I> <I>b<I>ca-7a2a-<I>-9d3b-<I>d<I>a<I>a9