function addLoadEvent(func)
{
    var oldonload = window.onload;
    if (typeof window.onload != 'function')
    {
        window.onload = func;
    }
    else
    {
        window.onload = function()
        {
            oldonload();
            func();
        }
    }
}

function addUnLoadEvent(func)
{
    var oldonunload = window.onunload;
    if (typeof window.onunload != 'function')
    {
        window.onunload = func;
    }
    else
    {
        window.onunload = function()
        {
            oldonunload();
            func();
        }
    }
}

var newwindow = '';
function popUp(url, id, width, height, scrolling)
{
    if (!newwindow.closed && newwindow.location)
    {
        newwindow.location.href = url;
    }
    else
    {
        newwindow=window.open(url,id,'height='+height+',width='+width+',scrolling='+scrolling);
        if (!newwindow.opener) newwindow.opener = self;
    }
    if (window.focus) {newwindow.focus()}
}