Error revealed but not sure whats causing it

[jamesie]

in config.inc.php I set line
@ini_set('display_errors', 'on ');
to show errors because my pages would not show

Now they show but I also found the error message:


Notice: Use of undefined constant _THEME_PROD_PIC_DIR_ - assumed '_THEME_PROD_PIC_DIR_' in /raid1/local/www/data-dist/prestashop/init.php on line 116

Notice: Use of undefined constant _PS_PRICE_DISPLAY_PRECISION_ - assumed '_PS_PRICE_DISPLAY_PRECISION_' in /raid1/local/www/data-dist/prestashop/header.php on line 18

Not sure what has caused this....