Postfix possibly ignoring myhostname and mydomainname?

[Edd]

Hi,
I want postfix to send email from a domain name different to the one that
it really is. This is because I have no real (as in on the net) domain
associated with it, so I am going to use my website address so that the
from field resolves and relays are happy to pass on my mail.

I have:

set myhostname to:
hitbox.arameus.net

set mydomainname to:
arameus.net

and added this line:
masquerade_domains=hitbox.arameus.net

So my theory is that postfix will send from uid at arameus.net

then restarted postfix. (postfix reload).
A quick 'postconf -d | grep my' reveals that postfix is infact ignoring
completely the value I have given it! why so?

Sorry if this is a really obvoius mistake, but I am new to mail server
administration, and I have checked the documentation and FreeBSD
mailinglist without luck.

Someone has suggested relaying between these two domains, so I added
relay_domains = arameus.net

Still no luck Im afraid.

Thanks all!