In order to define the rule login to the Webadmin interface and navigate to: 

Security & Filtering -> Acceptance & Routing -> Advanced Settings

Add a new rule:

Type a suggestive name for the rule

In the Conditions area leave:

Match any email message

or you can add conditions to match only the desired messages.

In the Actions area select:

Recipients - Add Recipient  -

                     a) Name:         %currentRcptLocalPart%@[IP or domain]                      

                     b) Folder:         leave empty

Repeat step 3. if necessary.

Note: %currentRcptLocalPart% will expand to the local part of the recipient address. For example if Axigen receives a message for axigen_user@localDomain.tld the variable will expand to axigen_user.

Note: [IP or domain] - replace this with one of the following:

IP address of the remote server; the IP must be enclosed between square brackets: [a.b.c.d]

domain name if you need to send the message to the same user but a different domain and you do not know the IP address. Axigen will use the DNR service to resolve the domain name.