Those html files invoke a shell script that calls the program below...
#!/bin/sh
# cpanel3 - edcron Copyright(c) 1997-2000 John N. Koston
# All rights Reserved.
# [email]bdraco@darkorb.net[/email] [url]http://cpanel3.darkorb.net[/url]
action=`echo "$1" | awk -F: '{ print $1 }'`
file=`echo "$1" | awk -F: '{ print $2 }'`
entry=`echo "$1" | awk -F: '{ print $3 }'`
crontab=`crontab -l | grep -v "^#"`
if [ "$action" = "a" ]; then
crontab=`echo -e "$crontab\n$entry"`
echo "$crontab" > ~/.crontab
crontab ~/.crontab
rm -f ~/.crontab
echo "$entry" > $file
fi
if [ "$action" = "d" ]; then
entry=`cat $file`
crontab=`echo "$crontab" | grep -v "$entry"`
echo "$crontab" > ~/.crontab
crontab ~/.crontab
rm -f ~/.crontab
fi
if [ "$action" = "c" ]; then
crontab=`echo "$crontab" | grep -v "$entry"`
echo "$crontab" > ~/.crontab
crontab ~/.crontab
rm -f ~/.crontab
fi