Help~ How do I redirect from https://domain.com to https://www.domain.com

[walay]

Help~ How do I setup to redirect from https://domain.com to https://www.domain.com

I tried to modify .htaccess but does not help.
and inside cpanel, all I could find is to redirect http.

I setup a Draupal site, everything works fine, however when in a secure page, whenever I try to submit/save something, it take me from https://www.domain.com to https://domain.com.

So I thought setting a redirection like that would be alot easier.

[djn]

Try putting this into .htaccess:

RewriteEngine On
RewriteCond %{SERVER_PORT} 443
RewriteRule ^(.*)$ https://www.domain.com/$1 [R,L]