$(this).attr() trouble

[lilmousiee]

$(document).ready(function() {
	$(".alert").click(function() {
		{
			var id = $(this).attr("id");
			alert(id);
			$(id).dialog();
			return false;
		}
	});
});

Ok it's alerting the id AFTER it alerts an undefined.. so it alerts "undefined" and then "5" or whatever the number may be.
What am I doing wrong?

[VIPStephan]

How many elements with class “alert” do you have in your document? Maybe the first match doesn’t have an ID?

Also, IDs must not start with a number, only with letters A–Z or a–z.

[devnull69]

If your id=="5" (which is not a proper id), what the heck do you expect

$(id).dialog()

to do?