crontab, PHP and MACOSX

Hello all, I don't know if it's the correct list, but as a php script is involved.... I try to start a set up a crontab job with crontab -e, which should start a php script: */10 * * * * cd /Users/yvan/Sites/est-pac/ ; /usr/bin/php /Users/yvan/Sites/est-pac/controller.php but nothing happens, and in the /etc/crontab or in /private/etc/crontab the job is not listed. As I am using Mac OS 10.4.9, should I use launchd? or does someone use crontab with a mac? I try a GUI application called CronniX to setup the job but without success. Any hints? Thanks in advance for your time and help. cheers yvan