[NTG-context] Eliminating orphans/widows when grid is on

Dear All, when the grid is switched on in my document, there are lots of orphan and widows in the output. \setuplayout[grid=yes] % grid=tolerant doesn't help According to the manual the grid typesetting is a solely ConTeXt feature not available in the core TEX. Is it production ready? Are there any options to handle o/w correctly? Thanks, Jan