Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.265
diff -u -p -r1.265 form.inc
--- includes/form.inc	4 Feb 2008 10:23:32 -0000	1.265
+++ includes/form.inc	4 Feb 2008 23:50:41 -0000
@@ -667,7 +667,7 @@ function _form_validate($elements, &$for
       // We only check for trimmed string length being zero. 0 might be
       // a possible value with some field types, such as radio buttons, so
       // empty() is not usable here.
-      if ($elements['#required'] && strlen(trim($elements['#value'])) == 0) {
+      if ($elements['#required'] && (!count($elements['#value']) || (is_string($elements['#value']) && strlen(trim($elements['#value'])) == 0))) {
         form_error($elements, $t('!name field is required.', array('!name' => $elements['#title'])));
       }