I have a new Drupal 7 site at mysite.com (address changed) - a CentOS 5.5 Linux machine in my full control.
By reading registration mails (they run through my Gmail account) I've noticed, that Drupal spammers seem to refer to my site via the address forum.mysite.com. Since any requests to a subdomain.mysite.com are redirected by my hoster to mysite.com, this works for them.
I wonder, if anyone has noticed same pattern (seems to be some common spammer tool behaviour) and what have you done? I'm thinking of using mod_rewrite to block access to forum.mysite.com, but maybe there is a better way? (Because I'm not sure if that spammer tool will go away if I close access to forum.mysite.com).
I've also thought of maybe changing my httpd.conf somehow:
ServerAlias mysite.com *.mysite.com
I'm not asking about Mollom or Captcha modules, because they seem to be not-up-to-date for Drupal 7 yet. And the spam users aren't a too big problem for my site anyway, because it has a card game embedded at the front page and I have a cron job deleting users not playing that game.