[jQuery] additional events

[alife]

hey,

my problem:

with the following code I put a TR in my table. in this TR I have
further (".button_plus") - elements. I want that the user is able to
click on these further elements. how could I realize that?
$(document).ready(function() {
$(".button_plus").click(function() {
                $(this).load( "ajax.php", {template: "testTR"}, 
function(output){
                                $(this).parent().parent().after(output);
                                styleTables();
                        }
                )
        });
 });

//ajax.php returns this:

<tr>
                                <td><input name="" type="text" value="Eintrag" 
/></td>
                                <td><input name="" type="text" value="Eintrag" 
/></td>
                                <td><input name="" type="text" value="Eintrag" 
/></td>
                                <td><img class="button_minus" 
src="images/button_minus.png" />
<img class="button_plus" src="images/button_plus.png" /></td>
                        </tr>

I hope you can help me, thank you in advance,

alife