HI all,
Authentication systems based on HTTP_REFERER checking are not really secure as it can be Spoofed easily using custom HTTP headers. A simple
googling for HTTP_REFERER gives the first link titled "How to spoof HTTP_REFERER".
So I changed something there in the above script file

Change "Your Ip here" to the IP address whom u want to allow access.
BUT,
If you
really need a secure system, u can use Apache .htaccess password protection techniques. You can see one tutorial
here.
If you are not using apache at all, try php session varibles to authenticate users.
(is that so general?. this is my first post. So plz dont flame me.
)