Problema con alcuni clienti

[10anniavanti]

con alcuni miei clienti ho il seguente errore quando li seleziono dall'admin/clienti:

Warning: array_merge() [function.array-merge]: Argument #1 is not an array in /work/www/virtualhost/www.safarasoftair.com/admin/customers.php on line 733

Warning: array_merge() [function.array-merge]: Argument #2 is not an array in /work/www/virtualhost/www.safarasoftair.com/admin/customers.php on line 735

Warning: reset() [function.reset]: Passed variable is not an array or object in /work/www/virtualhost/www.safarasoftair.com/admin/includes/cl ... t_info.php on line 17

Warning: Variable passed to each() is not an array or object in /work/www/virtualhost/www.safarasoftair.com/admin/includes/cl ... t_info.php on line 18

altri invece non visualizzano questo errore, ma vengono visualizzato correttamente.

Come posso risolvere?