Mod rewrite domain.com to www.domain.com, how ?

Hi,


What would be the rule in htaccess to make everyone who types domain.com automatically bring to www.domain.com ?
Is this a problem for the search engines ?

 

RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} !^www\.domain\.com
RewriteCond %{SERVER_PORT} ^80
RewriteRule (.*) http://www.domain.com/$1 [R=301,QSA,L]

 

Thanks maiahost, that works