[NTG-context] path for luatex cache

Hi, What should I do please, to prevent ConTeXt from creating $HOME/luatex-cache? I tried: - TEXMFCACHE=/opt/context/tex/texmf-cache - TEXMFVAR=/opt/context/tex/texmf-cache - LUATEX_CACHE=/opt/context/tex/texmf-cache/luatex-cache but without success... TIA for any help, -- Peter