I have a function to check my db for existing email addresses.  I'm having problems trying to figure out how to get a boolean value out of the success function.  I know that "exist" is out of scope, so that value can never be true.  Any hints?

 

        function checkExistingEmail(obj) {
            var exists = false;
            $.ajax({
                type: "POST",
                url: "CheckExistingEmailAddress.php",
                data: {check: obj.val()},
                success: function(msg){
                    if (msg == "TRUE") {
                        updateTips("<li>This email address has already been registered.</li>");
                        exists = true;
                    }
                }
            });
            alert(exists);
            return exists;
        }