I need to create a redirect so that the URL
That's the only URL I need to redirect (the rest of domain1.mysite.com stays where it is). There is only one htaccess file for the whole site (www.mysite.com, domain1.mysite.com, domain2.mysite.com, etc), so I can't just redirect
www.mysite.com/user/register shouldn't be redirected.
(I could probably figure this out eventually but mod_rewrite rules and the flu don't mix.)