The tide of unsolicited emails flooding into corporate and consumer inboxes is becoming a serious issue.

For consumers, emails inviting them to buy Viagra, extend their manhood or buy into a money laundering scam can be embarrassing, especially if landing in the inboxes of young children.

Employees waste increasing amounts of their time deleting junk emails. According to anti-spam company Brightmail, pornographic spam has increased by 380 per cent since November 2001.

It filters more than 55 billion messages each month for spam and estimates that 45 per cent of all email is unsolicited.

Microsoft blocks about 2.4 billion junk emails a day, some 80 per cent of the messages that hit MSN servers. BT Openworld estimates that, of the 25 million emails that it monitors, 41 per cent is spam.

Worse, these emails are creating a corporate headache for IT managers, as they seek to limit the number of spam emails clogging the company network. There is also the fear that such emails could hide viruses which then infect the network.

Now, industry is beginning to fight back. Companies such as Microsoft, AOL and Yahoo are joining forces to reduce the ability of spammers to use their email services to send junk mail.

Persistent offenders face tough crackdowns, and consumers and businesses will be able to sue senders of unsolicited emails and text messages under new proposals from the Department of Trade and Industry.

The problem is now considered so bad that even parliament is getting involved. It intends to hold a junk email summit in July to discuss the problem.