Apart from Warren's excellent advice, the source of your problem is
things like this:
'$_POST['vorname']'
How is PHP supposed to know that this is nested parentheses? You should
have done it like this:
"$_POST['vorname']"
Though of course, follow Warren's advice, and don't do it like this a
You have just done two things that make your site vulnerable to hacks.
Register globals means that someone can load a copy of your form to their
machine, modify it to include variables that you use internally like
$user_type = "admin" (or whatever) and post their form to your site, and
even though
