not 100% sure if this is what you are talking about, but,
iirc, 'domain
forwarding' is an option available in good DNS management
control
panels, which, depending on settings, this can forward the
request to
another domain without changing the domain name displayed in
the address
bar, so that all request to www.agent-in-manchester.com will
be
forwarded to www.main-agent.com, but users will still see
"www.agent-in-manchester.com" in their address bar.
hmm... on the second re-read of your post, it seems like this
is exactly
what you are doing already... is it?
Azadi Saryev
Sabai-dee.com
http://www.sabai-dee.com/