What I have done is actually to modify it so that you could use a redirect from somehost.foo.com to mainsite.foo.org/some/url/
This has some disavantages, like if you want to preserve the hostname somehost.foo.com in the address bar of the users' browser, you can't do that with my modified version. Also, at this stage, my version only redirects domains, without taking care of path or query strings, i.e. you can't do something smart like somehost.foo.com/somepath/here?somequery=string to mainsite.foo.org/some/url/somepath/here?somequery=string. Why I didn't do this? because I think that it can be tricky and confusing and really, we didn't needed it @ Greenpeace.
Do you want to get the small modifications I did?
