By Mark Ward Technology correspondent, BBC News website

Footage of Ms Cicarelli has spread widely online

Few people would regard judges as high-priests of hi-tech but they do seem to have recognised something that Daniela Cicarelli and Brazilian banker Renato Malzoni have yet to appreciate.

And that is the near impossibility of trying to stop illicitly taken photos or video circulating online.

As Ms Cicarelli and Mr Malzoni have learnt to their cost, every attempt to get material removed - in this case a grainy video of the two enjoying each other's company on a Spanish beach - only alerts a new audience to the existence of the footage.

Many judges in the UK and US do not issue injunctions to stop material being distributed because they know it is futile, says Nick Lockett, a senior partner at London firm DLL Legal and an expert on technology law.

"Instead," he said, "they will deal with it by claims for damages."

"That's the only recourse they are going to have," said Mr Lockett.

Paper plain

The situation is radically different than in the days when compromising images were likely only to be published in a newspaper.

In such a situation, said Mr Lockett, an injunction would serve because there was a finite number of newspapers involved. Pulp all those and the image is gone.

The net makes it hard to control who sees what

By contrast on the web, images and video clips can be copied an almost infinite number of times making any attempt to get them all deleted pretty much doomed to failure.

The saga began in September 2006 when lawyers for Ms Cicarelli and Mr Malzoni took action against Brazilian websites Globo and IG as well as video-sharing site YouTube requesting them to remove the clip of the couple.

They all complied but time and again the clip has popped up on YouTube as users of that site re-post it.

The latest ruling, following legal action begun by lawyers acting only for Mr Malzoni, demands that YouTube find ways of permanently stopping the video being uploaded.

Included in this ruling were fixed line phone firms some of whom are now reported to be blocking all access to YouTube. However, the clip is known to be on many other websites, available on file-sharing networks and is being passed around via e-mail.

The broader ban was brought about in case YouTube failed to find a way to stop users uploading the clip.

The prospects of YouTube managing this feat are perhaps slim given that it is already late with a software system it promised would automatically scan uploaded video to see if it was copyrighted material or not.

The system was first mentioned in September 2006 and was scheduled to be working by 1 January 2007. However, there is no sign of it being implemented yet.

If it does fail, Mr Malzoni's lawyer is calling for it to be fined $119,000 (�61,735) for each day the video has been viewable.

Legal rumble

A trio of Brazilian judges are reviewing the judgement to decide whether to make it permanent and whether to fine the video-sharing site.

Google paid $1.65bn to snap up the YouTube site

Mr Lockett said the claim for damages hinges on whether the Brazilian court has jurisdiction in the US where YouTube's servers are located.

In similar cases in the UK, British courts have said they have jurisdiction anywhere in the world.

But, he added, the legal action will also have to demonstrate that YouTube has not taken effective action to remove the clip.

The US Digital Millennium Copyright Act absolves all net companies from the need to police content as it is uploaded.

However, said Mr Lockett, once a company has been put "on notice" about a clip, they have to act fast.

In the UK and US, companies have little defence once they are notified about offending content, said Mr Lockett. Defending itself in a statement YouTube said: "We have people reviewing flagged content 24 hours a day, seven days a week and work hard to streamline the notification process by providing tools for people to alert us."

It added that more than 65,000 videos were uploaded to its site every day. But sheer popularity is no defence. "That's just tough," said Mr Lockett.

What may work in YouTube's defence is the fact that there are just so many copies of the clip online. If the damages claim comes to court, YouTube could argue that the numbers of people that saw the video clip via its site was small compared to the entire global audience. This could water down any claim for damages.