<input type="text" name="test[text]" >

<?php var_dump($_POST['test']); ?>

yada tam tersi

<input type="text" name="text[test]" >
<input type="text" name="text[test1]" >
<input type="password" name="password[pas1]" >
<input type="password" name="password[pass2]" >
<?php var_dump($_POST['test']); ?>

imkansız diye birşey yoktur ^^