If you have unix-style commands available to you, and the cron scheduling tool, you can configure cron to run this command daily, which deletes files that were created x days ago:
find /tmp/ -name FILESPEC -ctime +x rm -f {} \;
PLEASE BE EXTRAORDINARILY CAUTIOUS WITH THIS COMMAND, AS IT FORCES FILES TO BE DELETED.
Set FILESPEC to the file specification you want to use ("*.AOD") and 'x' to the number of days you want files to exist.
-JD.