I've modified a plugin that uses WP 2.1 builtin pseudo cron features. But never could see the timers work. So I started to debug and found that timers do work, but the cron (/wp-cron.php) never gets executed. I found this out by manually running it. Then when I modified wp-cron.php to output debug info to a file and now I'm sure that it's never executed from spawn_cron() function (tho spawn_cron says it did open a socket OK). I'm not using SSL or anything that could prevent the opening of socket. What can be the problem?