stick this into your root .htaccess file
Code:
RewriteEngine on
RewriteBase /
RewriteCond %{QUERY_STRING} (^|&)m=0(&|$)
RewriteRule ^ - [CO=mredir:0:www.example.com]
RewriteCond %{HTTP:x-wap-profile} !^$ [OR]
RewriteCond %{HTTP:Profile} !^$ [OR]
RewriteCond %{HTTP_USER_AGENT} "acs|alav|alca|amoi|audi|aste|avan|benq|bird|blac|blaz|brew|cell|cldc|cmd-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "dang|doco|eric|hipt|inno|ipaq|java|jigs|kddi|keji|leno|lg-c|lg-d|lg-g|lge-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "maui|maxo|midp|mits|mmef|mobi|mot-|moto|mwbp|nec-|newt|noki|opwv" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "palm|pana|pant|pdxg|phil|play|pluc|port|prox|qtek|qwap|sage|sams|sany" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "sch-|sec-|send|seri|sgh-|shar|sie-|siem|smal|smar|sony|sph-|symb|t-mo" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "teli|tim-|tosh|tsm-|upg1|upsi|vk-v|voda|w3cs|wap-|wapa|wapi" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "wapp|wapr|webc|winw|winw|xda|xda-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "up.browser|up.link|windowssce|iemobile|mini|mmp" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "symbian|midp|wap|phone|pocket|mobile|pda|psp" [NC]
RewriteCond %{HTTP_USER_AGENT} !macintosh [NC]
RewriteCond %{HTTP_HOST} !^m\.
RewriteCond %{QUERY_STRING} !(^|&)m=0(&|$)
RewriteCond %{HTTP_COOKIE} !^.*mredir=0.*$ [NC]
RewriteRule ^ http://www.example.com/mobile [R,L]
change
www.example.com on Line 4 to your domain name. On the last line, change to your mobile website! Anytime someone views your site from a mobile device they will be forwarded to the domain name you specify on the last line!