The alleged outburst by Microsoft chief Steve Ballmer a couple of years back that he was "going to f***ing kill Google" would suggest that the Redmond giant would go out of its way not to work with the then internet upstart.

But Trinity College Dublin is now in the unusual position where its student e-mail is delivered by a combination of Google and Microsoft technology.

It has just announced a major reduction in the amount of spam passing over its network thanks to the implementation of a hosted e-mail service from Microsoft.

Spam had been an acute issue for TCD. Of the 20 million e-mails passing across its network every month, some 80 per cent were spam. According to John Murphy, deputy director of IS services at TCD, this was a major problem, as the college's 20,000 staff and students are increasingly reliant on e-mail.

Spam was particularly bad late last year when TCD became the first university in Europe to sign up with Google to implement the Google Gmail tool to deliver messages to its own domain.

"We had to tackle the spam problem first or people would have stopped using their tcd.ie e-mail addresses," says Mr Murphy.

TCD looked to Microsoft's new managed service for messaging, Exchange Hosted Services. All TCD e-mail is now first filtered through Exchange mail servers running in a Microsoft data centre.

The service was initially deployed on a couple of servers as a pilot and the results were impressive and immediate.

"Over 20 days 12.1 million e-mails were sent to addresses in the TCD domain. The service managed to block 11.1 million spam messages, or 92 per cent of all incoming traffic," he explains.

A contract was put in place which carries a service level agreement that Trinity will get 100 per cent virus protection and a minimum of 95 per cent spam filtering.

"Exchange Hosted Services has restored people's faith in our ability to deliver an e-mail service," says Mr Murphy.