Has ConTeXt any support for producing a PDF with "optional content groups" (OCGs)?

In Adobe's jargon OCGs are also known as "layers" (not to confuse with layers in ConTeXt). See Section "4.10.2 Making Graphical Content Optional" in the PDF Reference 1.7 available at http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/pdf/pdfs/pdf_reference_1-7.pdf

I cannot find anything on the Wiki nor in the ntg-context emails and grepping through the source code for "ocg" does not give reasonable results.

Cheers,

Christoph