Modeling a friend class relation

[Ale Strooisma <a strooisma student utwente nl>]

Hi all,

I am creating all of the diagrams for my masters thesis in dia. This includes some UML class diagrams. In one of those class diagrams I'd like to indicate that one of the classes is a friend class an other one. I don't think the UML standard defines a notation for this. Does anyone have an idea what would be a nice way to model this? Or should I leave it out and only mention it in the text?

I realize this question might be a bit off-topic, but I guessed this would be one of the best places to get advice.

Kind regards,
Ale Strooisma