I got it working, thanks guys. I guess this works well for anyone that needs.
So this is the "user.php" in the Milk demo for Jquery validation plugin..
users.php (original)
<?php
$request = trim(strtolower($_REQUEST['login']));
//sleep(2);
usleep(150000);
$users = array('asdf', 'Peter', 'Peter2', 'George');
$valid = 'true';
foreach($users as $user) {
if( strtolower($user) == $request )
$valid = 'false';
}
echo $valid;
?>
User.php (with mysql results being matched for duplicates)
<?php
$link = mysql_connect('localhost', 'username', 'password') or die('error');
@mysql_select_db('databasename',$link) or die('error');
$valid = 'true';
$request = trim(strtolower($_REQUEST['login']));
//sleep(2);
usleep(150000);
$users = array( );
$query = mysql_query("SELECT login FROM members");
while ($row = mysql_fetch_array($query))
{
$memberlogin = mysql_real_escape_string(trim($row['login']));
$users[] = $memberlogin;
foreach($users as $user)
{
if( strtolower($user) == $request )
$valid = 'false';
}
}echo $valid;
?>