PREUN

/bin/sh

umask 022
if [ "$1" = "0" ]; then
	while read SHNAME; do
		[ "$SHNAME" = "/bin/ksh" ] ||\
		[ "$SHNAME" = "/bin/sh" ] ||\
		echo "$SHNAME"
	done < /etc/shells > /etc/shells.new
	mv -f /etc/shells.new /etc/shells
fi

POSTIN

/bin/sh

umask 022
if [ ! -f /etc/shells ]; then
	echo "/bin/ksh" > /etc/shells
	echo "/bin/sh" >> /etc/shells
else
	while read SHNAME; do
        	if [ "$SHNAME" = "/bin/ksh" ]; then
                	HAS_KSH=1
	        elif [ "$SHNAME" = "/bin/sh" ]; then
        	        HAS_SH=1
	        fi
	done < /etc/shells
	[ -n "$HAS_KSH" ] || echo "/bin/ksh" >> /etc/shells
	[ -n "$HAS_SH" ] || echo "/bin/sh" >> /etc/shells
fi