Hmmm, to do it from cron, install PHP as a system binary, and transfer your code to a "shell" type script written in PHP:
#!/usr/local/bin/php
MyPHPScript();
//or whatever code you have to do this task...
I have also seen folks suggest having a script trigger a certain action each time (or the first time) that it is loaded each day. That's kind of an interesting thought, but you'd have some guesswork in there, I guess:
BOSS: When will the logs come in?
YOU: Whenever, sir.......