Using a listbox in a form mail

Ok, This is a partial of the code:

send_bmc.onRelease = function() {
response_txt.text = ‘’;
var ok = true;

_lv.name = name_txt.text;
_lv.subject = subject_txt.text;
_lv.message = message_txt.text;
if (ok) {
	response_txt.text = "Sending...";
	_lv.sendAndLoad("sendemail.php", _lv, "POST");
}

};

And I have this to load my vars:
_lv = new LoadVars();

For that example, I have text inputs labeled “name_txt, subject_txt, and message_txt” and I have a button labeled “button_bmc”

I hope it makes somewhat of a sense. Right now, the form does work and now I want to add a listbox. I want to able to call on whatever the selected items are in the listbox. Thanks in advance,

Andre