SEO friendly redirect + questions

[valdet]

Hi there,
I am facing a similar issue here.

I managed to redirect from http://domain.net to http://www.domain.net with this htaccess trick

RewriteEngine On
Rewritecond %{http_host} ^yoursite.net
RewriteRule ^(.*) http://www.yoursite.net/$1 [R=301,L]

My question is how can I redirect http://domain.net/forum to http://www.domain.net/forum ?

The code below does not seem to work.

RewriteEngine On
Rewritecond %{http_host} ^yoursite.net/forum
RewriteRule ^(.*) http://www.yoursite.net/forum$1 [R=301,L]

Any clues...

Thanks