[NTG-context] Page numbering and first page

Hello Is it any way to get a different page numbering for the first page (and different heads and foots). I used to do in plain tex with a test : ********************************************* \newif\ifpageun \ifnum\pageno=1 \pageuntrue \else \pageunfalse \fi \footline={\ifpageun \hfil \global \pageunfalse \else \numpage=\pageno \advance\numpage by \decale \ifodd\numpage\rm \the\nom \hfill --page \the\numpage-- \else \rm --page \the\numpage--\hfill\the \nom \fi \fi} ********************************************* (names are french) but maybe there is a simpler way in Context.