mod_jk produces Error smh errno=13
The correct answer is online:
http://www.laliluna.de/articles/2008/09/14/apache_tomcat_mod_jk_selinux.html
The part you need is near the bottom, which I will copy and paste here in case that page goes away:
# mkdir /var/run/mod_jk
# semanage fcontext -a -t httpd_var_run_t "/var/run/mod_jk(/.*)?"
This apparently configures SELinux to allow mod_jk to work. It worked for me anyway.
Your OS might prevent access to the shared memory file. Try adding
# Set this to a location allowed to the 'Apache' user
JkShmFile /var/log/httpd/mod_jk.shm
in your mode-jk.conf
(I am using the filename spelling from your post but it might be mod_jk.conf or similar)
Are you using selinux? If you are, you might want to check on it being an selinux context problem.