If your site can be accessed as both
http://www.domain.com/ as well as
http://domain.com/ and are having trouble with things such as cookies on the Netscape browser*, here is a little rewrite rule you can place in your httpd.conf or on a per directory basis using .htaccess.
Here is what happens. When you request a page such as
http://domain.com/x.html, the rewrite engine checks to see if the HTTP_HOST does not match the fully qualified domain name (FQDN) which in this case is
www.domain.com. If they do not match, the engine rewrites the URL with the SERVER_NAME value, so make sure that your SERVER_NAME in your httpd.conf is the FQDN.
RewriteEngine On
RewriteCond %{HTTP_HOST} !www.domain.com
RewriteRule ^.*$
http://%{SERVER_NAME}%{REQUEST_URI} [R]
*About the Netscape Cookie Problem: If you issue a cookie from
www.domain.com using a string such as "domain=.domain.com", it cannot be read by domain.com, fred.domain.com, and so on. MSIE does not have this trouble. If you force all your URLs to start with www. and issue the cookie using domain=www.domain.com, this resolves the problem