Apache 2.2 include common data

I have a set of sites co-hosted in one of our development servers.

I need to configure to ALL of those sites the

Allow from 

directive. Since this is about dynamic IPs, that change relatively frequently, I need to setup a way in order to easily modify them.

Example:

<VirtualHost *:443>
    ServerName dbhost.domain
    ServerAdmin webmaster@domain
    DocumentRoot /srv/www/dbhost
    DirectoryIndex index.php index.php3 index.php4

    SSLEngine On

    <Directory /srv/www/dbhost>
            order deny,allow
            allow from 192.168.0.0/16 <subnet1> <subnet2> <subnet3> <etc...>
            deny from all
            AllowOverride None

            AuthType Digest
            AuthDigestAlgorithm MD5
            AuthName "devs"
            AuthDigestDomain /
            AuthDigestDomain /
            AuthDigestProvider file
            AuthUserFile <pwdfile>
            Require valid-user
    <Directory>

So, I want to include that "order/allow" in an external file, so I will be able to to easily use it to all configuration files and change it just once.

So, I created a new file that had the following lines:

 order deny,allow
 allow from 192.168.0.0/16 <subnet1> <subnet2> <subnet3> <etc...>
 deny from all

And then, I modified the directive as:

    <Directory /srv/www/dbhost>
            Include /fullpath/to/acl.conf
            AllowOverride None

However, apachectl -t reported errors:

apache2ctl -t
Syntax error on line 1 of /fullpath/to/acl.conf:
order not allowed here

So, is there any other way to do that?