Create PDF Annotations with Quartz (iOS)

Did anyone manage to write custom annotations in a existing PDF using Quartz? I have rendered an PDF using CGPDFDocumentRef etc, works fine now :) And i'm successful reading the Annots dict using

    if(!CGPDFDictionaryGetArray(pageDictionary, "Anno开发者_运维百科ts", &outputArray)) { ....

But i can't get my head around, how to write new annotations ..

Hmmm, no-one?? it can't be impossible ... :(

As stated in the Quartz 2D Programming Guide :

http://developer.apple.com/library/ios/documentation/GraphicsImaging/Conceptual/drawingwithquartz2d/dq_pdf/dq_pdf.html#//apple_ref/doc/uid/TP30001066-CH214-BCIFAFBC

You can use CGPDFContextSetURLForRect to add an annotations for an URL.