Custom WA hit log rotation

the logs are under /var/log/wa/access. the internal log rotation wasn't working for me so i wrote a custom script that was rotating the logs every three hours ( i removed the /etc/cron.hourly/wa_logrotate) but i have run into this use where the logs stop writing once the file size reaches 2 GB. i have increase the frequency to every 2 hours to counter that but may not be enough once our web traffic peaks in the school season. does anyone know if there is some limit of file size on the 3900s?