Use PureMessage with one of the following mail transfer agents:
See 'When should I use an existing sendmail, Postfix or Java System Messaging Server (JSMS) installation?' in the PureMessage FAQ for more information.
Oracle Communications Messaging Exchange Server: Although a version of Oracle Communications Messaging Exchange Server is not bundled with the product, PureMessage supports this MTA (if patched to include milter support). In order to use this MTA with PureMessage, you must configure it to communicate directly with the PureMessage milter. For instructions, see "Configuring PureMessage for Oracle Communications Messaging Exchange Server" in the Sophos Knowledgebase.