Need Help with Prepend AJAX

[gaza165]

below i am using this code to bring back chat posts from the database... i am prepending the result to a table... but what i want to do is make every other TR a different bg colour.

 

so like this

 

<tr class="second">NEWER POST</tr>

<tr class="first">First Post</tr>

 

because i am using prepend to put the latest record at the top of the table... im not sure how to add the class to each tr

 

function Get_Message() {
if(!locked){
$.ajax({
type: "GET",
url: "action/getmessages.php",
beforeSend: function(){
    // Handle the beforeSend event
    locked = true;
},
success: function(data){

	$('table.shoutbox').prepend(data);
	if(data != '') {
	PlaySound();
	}
	locked = false;

}
});
}
}