Theme Error line 1805

On a clean install of Drupal 6.9 I get the following error using Garland.

warning: Attempt to assign property of non-object in /home/her11754/public_html/coaching/includes/theme.inc on line 1805.

This refers to the following code line:

$variables['language']->dir = $GLOBALS['language']->direction ? 'rtl' : 'ltr';