.htaccess redirect for splogs

hi all, i was just wondering if anyone out there who knew about .htaccess files and the code that goes into them could take a peek at this and tell me if it will mess up a multisite install or if it’s actually a good thing.

# BEGIN ANTISPAMBLOG REGISTRATION
RewriteEngine On
RewriteCond %{REQUEST_METHOD} POST
RewriteCond %{REQUEST_URI} .wp-signup.php*
RewriteCond %{HTTP_REFERER} !.yourdomain.tld. [OR]
RewriteCond %{HTTP_USER_AGENT} ^$
RewriteRule (.*) http://someotherpage.tld/ [R=301,L]

i found it here and the code was written by D’Arcy Norman. (credit where it’s due!)

cheers.