[NTG-context] headers in PDF document

Hello, How can I add Author/Title/Creator/Keywords/... to PDF documents, possibly with non-ascii characters? In LaTeX the hyperref package does the job (with help of \pdfstringdef, which redefines a whole bunch of things). Most ConTeXt documentation contains these headers, but I haven't seen any examples in ConTeXt sources yet. Thank you, Mojca