this isn't an exact answer, but i might be able to point you in a correct direction . you might be able to do a mod-rewrite by doing a redirection based on rewrite conditions.
for example, we once used the following to send users to our non-https, www page if they enter on a https: url. fyi we use helicon's isapi mod rewriter at www.isapirewrite.com/
RewriteCond %{HTTPS} (on)?
RewriteCond %{HTTP:Host} ^(?!www.)(.+)$ [NC]
RewriteCond %{REQUEST_URI} (.+)
RewriteRule .? http(?%1s)://www.%2%3 [R=301,L]
