Execution Problems with Cron

Hi all!!
I have a nerve-wracking concept (probably for me!!) which is not understood. My crontab entry looks this way.

33 09 22 3 * /home/myexp.sh "Bgp4 ALL" >/dev/null 2>&1

But cron gets started occasionally. Sometimes it does. Sometimes it does not. And sometimes it hangs in the middle (I found by seeing the incomplete logs created by Bgp4).:wall: Please guide me as I am all new to cron and have no clue on why it behaves this way. I am using cron in linux (FC10 system).

Thanks.

Please check for cron daemon logs first.
Since you are saying it starts and runs at some arbitrary time which should not happen, try appending the timestamp in the output file when the script is triggered by the cron dameon, that should nail down the problem to an extent.