[Plugin: WP Super Cache] help,doesn’t work when wp in sub directory

I install wordpress in a sub directory ‘/home/www/wp’.
wp-super-cache doesn’t work, it always said:
<!– Dynamic Page Served (once) in 0.956 seconds –>
Can anyone help me? Thanks!!!

<VirtualHost *:*>
    ServerName www.domain.net
    DocumentRoot /home/www

    <Directory />
        Options -Indexes +FollowSymLinks +SymLinksIfOwnerMatch
        AllowOverride None
        Order Allow,Deny
        Allow from All

        RewriteEngine On

        RewriteBase /
        AddDefaultCharset UTF-8
        RewriteCond %{REQUEST_METHOD} !=POST
        RewriteCond %{QUERY_STRING} !.*=.*
        RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress|wp-postpass_).*$
        RewriteCond %{DOCUMENT_ROOT}/wp/wp-content/cache/supercache/%{HTTP_HOST}/$1/index.html -f
        RewriteRule ^(.*) /wp/wp-content/cache/supercache/%{HTTP_HOST}/$1/index.html [L]

        RewriteBase /wp/
        RewriteCond %{REQUEST_FILENAME} !-f
        RewriteCond %{REQUEST_FILENAME} !-d
        RewriteRule . /index.php [L]

    </Directory>

    <Directory /home/www/wp/wp-content/cache>
        AllowOverride None
        Header set Cache-Control 'max-age=300, must-revalidate'
        ExpiresActive On
        ExpiresByType text/html A300
    </Directory>