How can I put a watermark image on every page?

Hi

I am successfully using this package and I think it great.

I have now been told that:

> PDF content must have DRM (watermarks, social stamps) to ensure that the IP of content is protected.

I have some text available for each document that represents a copyright statement along the lines of:

```
copyright:'© My Group Publishing Limited'
```

Have you any idea how I would go about achieving this?

Thanks