Vanilla 2

Hi, I haven't understood on how to use prettyphoto with ajax request:

suppose my jquery function is

function ajax_call(param)
{
var url2Call = 'url2call';
$.ajax({
type: "POST",
url: url2Call,
data: 'param='+param,
dataType: "html",
beforeSend: function(xhr) {
xhr.setRequestHeader("Ajax-Request", "true");
},
success: function(response) {
// this is where I output response
},
failure: function(response) {

}
});
return false;
}

how to use prettyphoto[ajax] ?

I can't understand how href should be, because usually I call a js function.

Please note I'm using CodeIgnitier, but I don't know if could be related to any problem.

Thanks in advance for any response