Logrotate doesn't run hourly in Ubuntu 13.04

As per https://answers.launchpad.net/ubuntu/+source/logrotate/+question/238977 I am now creating a bug:

I am currently experiencing some issues with logrotate, and running them hourly. After some investigation I found the following:

/etc/crontab:
# m h dom mon dow user command
17 * * * * root cd / && run-parts --report /etc/cron.hourly
25 6 * * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
47 6 * * 7 root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly )
52 6 1 * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly )

ls /etc/cron.daily/
logrotate

ls /etc/cron.hourly/
# empty

I think that means the following logrotate will not work:

ls /etc/logrotate.d/nginx
/var/log/nginx/*.log {
  hourly
  # (...)
}

root@wilmut:~# lsb_release -rd
Description: Ubuntu 13.04
Release: 13.04

root@wilmut:~# apt-cache policy logrotate
logrotate:
  Installed: 3.8.3-3ubuntu2
  Candidate: 3.8.3-3ubuntu2
  Version table:
 *** 3.8.3-3ubuntu2 0
        500 http://us.archive.ubuntu.com/ubuntu/ raring/main amd64 Packages
        100 /var/lib/dpkg/status

Is there a reason why logrotate is not set to run hourly in Ubuntu?