diff --git a/booking.balance.inc b/booking.balance.inc
index d88612c..e392b42 100644
--- a/booking.balance.inc
+++ b/booking.balance.inc
@@ -14,6 +14,7 @@ function booking_balance_page() {
 	//verify that arg(1) is a uuid
 	if (! preg_match('/^[0-9A-Fa-f\-]+$/', arg(1))) {
 		//parameter from url is not what we were expecting
+		watchdog('booking', "Invalid token supplied to the balance payment page.");
 		drupal_set_message("Error: Invalid token supplied to the balance payment page. Please use the contact us form to let us know.", 'error', FALSE);
 		drupal_goto('<front>');
 		return "";
@@ -38,7 +39,7 @@ function booking_balance_page() {
 	$person = $query->execute()
 		->fetchObject();	
 	*/
-	
+
 	if ($person) {
 		//load all the fields
 		$node = node_load($person->nid);		
@@ -47,6 +48,9 @@ function booking_balance_page() {
 		//maximum length for invoice id in paypal is 127 characters so truncate if necessary
 		$invoiceid = substr($invoiceid, 0, 126);		
 	} else {
+    watchdog('booking', "<pre>Unmatched token supplied to the balance payment page:\n@info</pre>", array(
+      '@info' => print_r(arg(1), true)
+    ));
 		drupal_set_message("Error: Invalid token supplied to the balance payment page. Please use the contact us form to let us know.", 'error', FALSE);
 		drupal_goto('<front>');
 		return "";