After upgrading Apache to 2.2.23 there is a problem

Question

I (perhaps foolishly) upgraded Apache from 2.2.22 to 2.2.23 on OS X Mountain Lion Server. Following the upgrade, remote clients on the LAN cannot access the Web server's default.html.en web page. The DNS entries still look okay on OS X Mountain Lion Server.
Any ideas as to what might have got broken/overwritten by Apache by doing the upgrade that I need to fix or could something be blocking things?
Also, while probably not related, when, directly from the (updated) web server machine, I access 127.0.0.1 from within the web browser I can see the start up web page for Apache on OS X Server (so Apache is running, just can't be accessed remotely). However, when I try to access the same web page, again directly from the local web server machine, but this time using localhost instead of the IP address in the URL then the web page doesn't appear.
The hosts file on the web server has the following entries:
127.0.0.1     localhost
255.255.255.255     broadcasthost
::1             localhost
fe80::1%lo0     localhost

Answer 1

Yes, I should have backed up httpd.conf but unfortunately I didn't (it was a very long day). On the upside I am learning way more about httpd.conf than I ever thought I would.
After some soul searching I have since discovered that the ./configure string should also have had --disable-version in it. This is because it is a built-in module.
So a recompile of Apache and Apache is running and remote client machines can see 'html' based web pages. However, there remains a problem in that accessing php pages results in the php code being viewed instead of the web page. So something is still broken somewhere just not sure what. Any ideas? Please advise.
Below is a snippet of my httpd.conf RE the PHP side of things:
Snippet----------------------------
LoadModule php5_module        libexec/apache2/libphp5.so
#I have checked the libexec/apache2/libphp5.so exists. Still scratching head!
PHPIniDir “/etc/php.ini”
<IfModule php5_module>
    AddType application/x-httpd-php .php
    AddType application/x-httpd-php-source .phps
    <IfModule dir_module>
        DirectoryIndex index.html index.php
    </IfModule>
</IfModule>
Include /private/etc/apache2/other/*.conf
End snippet----------------------------
By the way, doing a 'php -v' gives me the following result in Terminal which I presume means that PHP is okay but for some reason Apache or the Server is missing something but I don't know what that might be
PHP 5.4.10 (cli) (built: Jan  9 2013 09:33:16)
Copyright © 1997-2012 The PHP Group
Zend Engine v2.4.0, Copyright © 1998-2012 Zend Technologies