diff --git a/booking.variety_form.inc b/booking.variety_form.inc
index 75a7e6f..9828e4d 100644
--- a/booking.variety_form.inc
+++ b/booking.variety_form.inc
@@ -123,7 +123,13 @@ function booking_variety_session_form_callback($form, &$form_state) {
 function booking_variety_regn_form_validate($form, &$form_state) {
 	global $event;
   $values = $form_state['input'];	
-  watchdog('booking_debug', 'booking_variety_regn_form_submit: <pre>@info</pre>', array('@info' => print_r( $form_state, true)));
+  watchdog('booking_debug', 'booking_variety_regn_form_validate: <pre>@info</pre>', array('@info' => print_r( $form_state, true)));
+
+  // Don't run validation on ajax callback
+  if (isset($form_state['input']['_triggering_element_name'])) {
+    watchdog('booking_debug', 'booking_variety_regn_form_validate: skipping due to ajax callback');
+    return;
+  }
 
   //verify that user-entered data is a number
   if (! preg_match('/^[0-9]+$/', $values['booking_nid'])) {