[NTG-context] \setuphead question

How do you obtain the same result as \setuphead[chapter][header=option(,footer=option)] ( option = none empty high nomarking ) in a document where [header/footer][left/rightedge]="not empty" on chapter pages i.e. only [header/footer][text]=option for chapter pages and others ( left/right edge ) are not modified ? -- Best, Alan * using ConTeXt ver: 2008.08.18 14:00 MKIV fmt: 2008.8.22 int: english/english (on Windows XP)