Node submission information missing, PHP error message instead.

Pages that include node submission information don't render properly, but instead show errors like

warning: Parameter 1 to phptemplate_node_submitted() expected to be a reference, value given in /Library/WebServer/Documents/includes/theme.inc on line 617.

It looks like the definition of function phptemplate_node_submitted() at template.php:176 is wrong; it is

function phptemplate_node_submitted(&$node)

but it should be

function phptemplate_node_submitted($node)

See also http://drupal.org/node/621946, http://drupal.org/node/613480, http://api.drupal.org/api/function/theme_node_submitted/6