Now apache 2.4 provide areal remoteIP software . It there will be enabled by default . You can check it as follows,

# httpd -l | grep mod_remoteip.c
mod_remoteip.c

If you get the above results that means the remoteip module already compiled and enable in apache. otherwise you can download it from

https://svn.apache.org/repos/asf/httpd/httpd/trunk/modules/metadata/mod_remoteip.c

And compile it as follows,

# apxs -cia mod_remoteip.c

You may now need to add the following lines to httpd.conf  for enabling this  REMOTE_ADDR with real visitor Ip as follows,

Add the following lines to httpd.conf

#LoadModule remoteip_module /usr/lib/apache/mod_remoteip.so    # This line only need if you compile this module alone
RemoteIPHeader X-Real-IP
RemoteIPInternalProxy X.X.X.X/24      # Your server IP address

Also please note this module is not available for  lower versions of apache like apache 2.2.x , for that you have to use the mod_rpaf module itself .