SplitDomain Bounce back

[rootdet]

Hello All,

I got the split domain setup working so that i will not have any delivery loops. However when it does not know of an address it returns the following error to the sender.

550 5.7.1 <test92@somedomain.com>: Relay access denied.

My setup is like this for the domain.

Mail -> Rackspace cloud (split Domain setup) -> zimbra

I would like to make it so that if Zimbra gets the message it knows The box is not at rackspace it returns the user message for something like "User User here by" or etc.

If people get Relay Access Denied they will assume its a problem wiht us when its the mailbox is not valid

Thoughts?

[rootdet]

When i am in Webmail and send a message i get this:

<george@mmcet.com>: host mx1.emailsrvr.com[72.4.117.21] said: 550 5.7.1
<george@somedomain.com>: Relay access denied. (in reply to RCPT TO command)

From a Rackspace side, George does not exiest and neither does it on Zimbra. So the error messages rather i send from the outside in, or from the inside out, is both the same.

So All Rackspace does is forward any message that does not have an account there over to Zimbra. I would expext Zimbra to know if its getting the message for and there is no user, it would reject it as user unknown.

Maybe it be possible to do a callout and then reject?