[Plugin: Login LockDown] via proxy, REMOTE_ADDR is changed

Accessing via a reverse proxy server such as apache with proxy_module,
“REMOTE_ADDR” is changed to the proxy itself.
I modified “REMOTE_ADDR” to “HTTP_X_FORWARDED_FOR” and it seems fine.
Is this a good way ?
Is this modifing make me more danger ?

http://wordpress.org/extend/plugins/login-lockdown/