diff --git a/s4.cgi.m4 b/s4.cgi.m4
new file mode 100755
index 0000000..741f33b
--- /dev/null
+++ b/s4.cgi.m4
@@ -0,0 +1,31 @@
+`#'!m4_indir(`_SHELL_')
+# 愛
+m4_changequote(``,'')mydir=`dirname $0`
+. $mydir/s4-funcs.sh
+
+cgiinit
+if [ -z "$guestonlymode" ]; then
+  if [ x"$1" = x"reg" ]; then
+    contenttype; echo
+    regist $2
+    putfooter
+    exit
+  fi
+
+  dologin
+fi
+
+case ${SERVER_SOFTWARE} in
+  bozohttp*)	# Ugly workaround for bozohttpd, which can't send
+    		# two or more arguments.
+    set -- `echo "$@"|(IFS=+ read a b c d e f g; echo $a $b $c $d $e $f $g)`
+    ;;
+esac
+
+# err 1=$1 2=$2 3=$3 4=$4
+stage=`getpar stage`
+stage=${stage:-$1}
+case ${stage} in
+m4_sinclude(_CASE_)esac
+
+putfooter