[syslog-ng]The syslog-ng process dies

Hello I have noticed this problem twice now- I start syslog-ng manually from a script with the following command : - syslog-ng -f /etc/syslog-ng.conf Syslog messages get logged in their respective files/directories. However, some time during the night, the syslog-ng process dies by itself - The command ps -aux |grep syslog-ng yields no process ID and the log files show nothing. Syslog-ng version is 1.5.9 Is this a bug ?? Regards Madhvi