// Configure these defaults for your site
var _POPUP_FEATURES = '';

// open a popup window
function popup(a, features) 
{
    if (isUndefined(features)) features = _POPUP_FEATURES;
	var theWindow = window.open(a.href, a.target || '_blank', features);
	theWindow.focus();
	return false;
}

// helper function
function isUndefined(v) 
{
    var undef;
    return v===undef;
}