PHP 5 cron jobs

I wrote a PHP script that uses PHP 5 functions (SimpleXML) to parse an RSS feed. I would like to set up a cron job to run this script, but using PHP on the command line invokes PHP 4, which can't run my script. What is the path to PHP 5, so that I may use it to run cron jobs?

Digging around, it looks like you could try:
/usr/local/php5/bin

btf