中文化的一些問題

Message
set_time_limit() has been disabled for security reasons in /home/xxxxxxx/public_html/includes/common.inc on line 2515.

Message
set_time_limit() has been disabled for security reasons in /home/xxxxxxx/public_html/includes/locale.inc on line 988.

這兩個訊息有個共通點
function drupal_cron_run() {
// If not in 'safe mode', increase the maximum execution time:
if (!ini_get('safe_mode')) {
set_time_limit(240); <=重點是這裡有錯誤
}

我怎樣都看不懂~麻煩請高手賜教~該怎麼修改