Microsoft has unveiled new tools for its Hotmail service, aiming to weed out the bulk of spam messages.

The software giant has released a preview version of Smart Network Data Services, which offers statistics about email being sent to Hotmail accounts.

The service shows the volume of email coming from single IP addresses, and whether Hotmail's filters have tagged it as spam.

Smart Network Data Services can help ISPs to identify accounts used to distribute spam emails, either deliberately or because they are infected by a virus and turned into a so-called zombie.

Microsoft also launched MSN Postmaster, a website where ISPs, email service providers and legitimate senders of bulk email can learn about spam issues.

Postmaster is intended to educate senders on how to prevent legitimate emails from getting caught in spam filters.

"MSN Postmaster and Smart Network Data Services represent a move towards broader, more comprehensive and transparent information sharing with ISPs and email senders to ensure that email continues to be an essential and valuable communications tool," said Kevin Doerr, product unit manager for MSN Hotmail at Microsoft.

"With over 200 million active email accounts worldwide, MSN Hotmail is in a unique position to collect and analyse email activity data.

"Working together, MSN Hotmail and service providers can make their customers happier and more satisfied with the services we all provide."

Postmaster and Smart Network Data Services are part of Microsoft's efforts to weed out spam. In June last year the company promised to filter out 98 to 99 per cent of all spam by June 2006.

The software vendor is involved in a series of projects, including Microsoft Smartscreen and Sender ID.

Sender ID tackles the problem of domain name spoofing, a technique used by spammers to hide the identity of the message sender. The technology checks whether the 'from' email address corresponds with the IP address from which the message originates.

Smartscreen is used to filter out phishing emails by rerouting them to the user's spam folder.