>> I want my Exim platform to act as an external filtering solution, mailboxes
>> being hosted on a remote server. That is,at the ACL level on receiving the
>RCPT
>> TO email address, to have it validate this very address against the remote
>> destination server.
>Why not verify recipient with callout?
Actually, this is a bit more complex than previously stated. The mailbox also
resides on our filtering plateform : when an incoming message turns up, a copy
of it is stored locally, and another one sent to the remote server. If this
latter one is down, our customers can come and check their incoming emails on
our platform using a webmail interface. So far, when a mailbox is created on the
remote server, the 'remote' administrator also has to declare the newly created
email address on our filtering platform (this action performs the local mailbox
creation). If not, we consider the email address non-existant.
From now on, I'd like this creation to be made automatically so the 'remote'
administrator should not have to worry about the declaration on our plateform.
That's why running a script at the ACL level would have done the trick : if the
recipient adress is unknown, verify it and if it succeeds, create the local
mailbox and deliver both copies of the message.
But callout may also do the trick. If the verification succeeds, I can set a
$acl_ expansion variable, which would trigger a router, before the ones that
deliver both local and remote copies, that creates the mailbox and do somme
other stuff. Does that sound good to you ?
