I just started learning YUI, to practice I put together the code below. How can I pass a specific argument - the "email" variable - to the handler?

Code:
YAHOO.util.Event.onDOMReady(init);

function validate_email(obj){
    var email_exp = new RegExp(/^[\w\.\-]+@([\w\-]+\.)+[a-zA-Z]+$/);
   /* 
    if (!email_exp.test(email.value){
	alert("Invalid Email Address");
    }
   */
}

function init(){
    var email = YAHOO.util.Dom.get("email");
    YAHOO.util.Event.addListener(email, "blur", validate_email);
}