Postini on Monday announced new features for its hosted messaging security and compliance services that add investigation management, encryption features, and better protection against Internet threats.

The new and upgraded services, slated for availability during the second quarter, are designed to help large organizations protect themselves from threats as well as manage and archive e-mail and instant messaging communications, according to company officials.

Enhancements to Postini’s archiving services include a new investigation management feature designed to ease the e-discovery process -- and comply with the new Federal Rules of Civil Procedure, for example. These rules, which took effect in December, require businesses to retain and be able to produce electronic records for courts and litigating parties.

New archiving features include the Postini Personal Archive and Postini Toolbar, which give an organization’s users access to archived e-mail and instant messages from their desktops without having to get the IT department involved.

New encryption features include the ability to send encrypted mail to consumers who can easily decrypt, view and reply to messages in their in-box, officials say. Postini already offers business-to-business encryption via its Transport Layer Security service.

On the e-mail security front, Postini has added adaptive heuristic algorithms that help protect against spam sent from bot nets, or armies of computers that have been compromised by malware and turned into spam servers. When the service detects multiple spam messages that contain the same content and are therefore likely sent from bot nets, it will place these messages in a “penalty box” for further examination. The service also features improved algorithms for catching image spam, the vendor says.