Omdat je met SMTP geen catchall adres hebt op een Exchange 2007 is er op Codeplex (OpenSource) een Agent geschreven die dit voor je kan afhandelen.

Catch All Agent

http://catchallagent.codeplex.com/

Project Description
An Exchange2007 Transport Protocol Agent which provides the (MTA) catchall functionality.

Description

Exchange2007 (like Exchange 2003) doesn’t provide CatchAll functionality. CatchAll is the ability of an SMTP server to redirect messages to non-existing recipients to a specific address.

This CatchAllAgent is an Exchange 2007 Transport Agent. The CatchAllAgent can be configured to redirect the recipient address for unknown recipients to a ‘catchall’ address such that such messages end up in a dedicated mailbox. The configuration allows for multiple domains, but you can only specify a single target address for each of those domains.