OT: when was ditto implemented in OS X?

[Tiemo Hollmann TB]

Hello,

does anybody knows by incident, in which OS X release ditto was implemented?
I just got doubtful because I have read something about min 10.4, but wasn't
sure about that source and didn't found any other docs in the net about
that.

I would like to set OS X min 10.3 as system requirements for my app. Am I on
the safe side with that for ditto?

Thanks

Tiemo