Directing mobile browsers to a WAP site
Typically, you will design a separate site for phones and mobile devices. Most designers create this site in a subdomain, and then redirect mobile browsers to the subdomain.
I suggest you use a web service to detect mobile devices for your site. This way you are current with the latest list of web browsers. You can find a service like this by searching at Google.
You can also find codes for .htaccess and PHP to use with your site, but those lists of browsers may need constant updates.