*/10 * * * * /usr/bin/lynx --dump /var/www/web4/web/scripts/admin/cronjobs.php > /dev/null
This can not work, you mx up http path's with filesystem path's. Lynx is a webbrowser.
Do you want to execute your PHP script in in your apache server or as a shell script. In shell scripts you can not use all php functions like e.g. header redirects, thats why I posted you above the instructions on how to execute your script in a browser.
Does it work if you execute this line on the shell:
/usr/bin/lynx --dump http://www.mydomain.nl/scripts/admin/cronjobs.php