Install vlogger:
aptitude install vlogger
Define a custom log format in /etc/apache2/httpd.conf:
LogFormat "%v %h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" vlogger
CustomLog "| /usr/sbin/vlogger -s access.log -t %Y%m%d-access.log /var/log/apache2" vlogger
Remove any custom log directives from virtual hosts and restart Apache:
/etc/init.d/apache2 restart