I upgraded to CiviCRM 4.6.4 on Joomla 3.4.2 after a year on older versions. I've cloned a previously working but expired event. Registration from the back-end works fine but from the front-end gives this error:
Fatal error: Call to undefined method CRM_Core_Payment_Form::setPaymentFieldsByProcessor() in /home/***/www/www/administrator/components/com_civicrm/civicrm/CRM/Event/Form/Registration.php on line 388
If I make it an unpaid event (Configure Fees with Paid Event = No), I get a different error:
Fatal error: Call to undefined method CRM_Core_Payment_Form::buildPaymentForm() in /home/***/www/www/administrator/components/com_civicrm/civicrm/CRM/Core/Payment/ProcessorForm.php on line 114
Advice please!