It seems that instead of screwing the staff group, changing the default values โโfor the default section solved the problem.
default:\ :path=/usr/bin /bin /usr/sbin /sbin /usr/X11R6/bin /usr/local/bin /usr/local/sbin:\ :umask=022:\ :datasize-max=infinity:\ :datasize-cur=infinity:\ :maxproc-max=256:\ :maxproc-cur=128:\ :openfiles-cur=128:\ :stacksize-cur=4M:\ :localcipher=blowfish,6:\ :ypcipher=old:\ :tc=auth-defaults:\ :tc=auth-ftp-defaults:
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