I suppose the error occurs at line 542 :
AddOutputFilter INCLUDES .shtml
First make sure the mod_include module is enabled. To do that, issue the
# a2enmod include
command as root. Then, restart with
# /etc/init.d/apache2 restart
Second, according to the documentation, you also need the "Includes"
option to directories containing shtml files. So you might have to add
the following line.
Options +Inculdes
More info : http://httpd.apache.org/docs/2.0/mod/mod_include.html#enabling
My guest is that the module is not enable, so the first step should fix that.
By the way, the "include" module is just for parsing shtml file. It
looks for