Código PHP:
Ver originalecho '
<html>
<head>
</head>
<body>
<FORM name="form1" ACTION="http://www.aaaaa.es" METHOD="POST" ENCTYPE="application/x-www-form-urlencoded">
<INPUT NAME="a" TYPE="hidden" VALUE="el que sea">
<INPUT NAME="b" TYPE="hidden" VALUE="el que sea">
<INPUT NAME="c" TYPE="hidden" VALUE="el que sea">
</FORM>
</body>
</html>
';
echo '<script>document.form.submit();</script>';