Done, slightly simpler but same idea. Thanks!

It is possible to have a number of date parts other than 3. For 
example, when initialising a form ($this):



     $this->addVariable(_("Start Date"), 'start', 'monthDayYear', true);

     $this->addVariable(_("Start Time"), 'start', 'hourMinuteSecond', true);



Which works as expected, but breaks the validation function, which 
should probably read:



     function emptyDateArray($date)

     {

         if (!is_array($date)) {

             return empty($date);

         }



         $empty = 0;

         $parts = 0;

         /* Check each date array component. */

         foreach ($date as $key => $val) {

             $parts++;

             if (empty($val)) {

                 $empty++;

             }

         }

         /* Check state of empty. */

         if ($empty == 0) {

             /* If no empty parts return 0. */

             return 0;

         } elseif ($empty == $parts) {

             /* If all empty parts return 1. */

             return 1;

         } else {

             /* If some empty parts return -1. */

             return -1;

         }

     }