WordPress MU

I've installed the reCaptcha plugin, activated it globally and gotten a global ey for it. However it doesn't work on blogs that exist in subdomains where it asks for the key again and users who have signed up with WPMU can see reCaptcha in their admin control panel. So how can I make it so that reCaptcha uses the global key for all the blogs without asking for it from individual blogs?

My other questoin is registration, I'm using WPMU with BuddyPress and I don't see reCaptcha at all in the BuddyPress registration page (i.e. /register) or the WPMU registration page (i.e. /wp-signup.php)

You probably need to talk to the developer of the plugin - its obviously not coded to realised that xx.yy.zz/aaa and xx.yy.zz/bb are in fact the same server.

I can probably hardcode in the key, my bigger concern is that it does not appear in either /register or /wp-signup.php ...