From Kaspersky Lab:
Kaspersky Security for Microsoft Exchange Server 2003 protects users of corporate mail systems against viruses, spyware and spam, and can be centrally administered. Kaspersky Security for Microsoft Exchange Server 2003 provides antivirus scanning of incoming and outgoing messages and mail stored on the server, as well as messages in shared folders. It also helps mail system users to block unwanted mail using intelligent spam recognition technologies in addition to technologies provided by Microsoft. Advanced technologies for protection against viruses and spam. In addition to its proven antivirus technologies that ensure traditionally high detection rates of malicious programs, the product makes use of the SpamTest technology to detect unwanted mail. Two-tier spam filtering. The product filters unsolicited mail in conjunction with Microsoft Exchange 2003 / Outlook 2003, guaranteeing high recognition of spam.