Super injunctions: How do those that are subject to it know about it?

This is a spinoff from the IMHO thread What do the dopers think of the Kate Middleton brouhaha. A (controversial) thing in English law is the privacy-protecting “super injunction”: A court ruling that prohibits not only media coverage of a particular story, but also of the existence of that court ruling itself.

These injunctions are issued in civil proceedings between two parties, but they’re not only binding as against the respondent but apply generally (in the Trafigura example, the ruling expressed this by saying that the injunction is addressed to “the person or persons unknown”). So how are the other media outlets that were not a party to the proceedings supposed to know about the injunction that they’re bound by?

So I’m assuming a lot of it happens via the traditional “old boys network” which is how all of this was handled back in the day. E.g. the “D Notice” system that was used to control release of sensitive information in the UK press, and absolutely relied on editors and proprietors being a good sport:

I guess if that fails then you find out when your boss gets a phone call from the lawyers. That is why the example in this case seems to have all the hallmarks of a super injunction. Its very likely the person writing the Guardian column reporting on what is said on the US talk shows would not be in the know, and so mention what Colbert said about the royal affair, then have to rapidly edit it after a phone call from the lawyers:

Not a law-talkin’ person; doubly so, not a UK law-talkin’ person, but this seems on-point:

In short, a privacy injunction binds anyone who is aware of it. A super-injunction, as a subset of privacy injuctions, does too. However, there is an obligation to notify journalists that the injunction exists.