None as far as I can see, provided you can live with a command-line browser (like lynx) or wget + some rewrite rules to run the cron jobs with these tools.
another one is to configure the apache rewrite rules to directly execute the cron php file (not letting it pass through the index.php script) when called over http. So no commandline php necessary. You can configure a cronjob entry with lynx or wget performing the http request to the cronjob's php file and dumping the output to /dev/null or some log file. I used that in the early days of ezp 2.2.X, now I compile me own php module and command-line client.
