function OpenDivCenter(divName, hideBackground)
{    
    var box = $(divName);
    if (hideBackground)
    {
        $('container').hide();        
    }
        
    
    var scroll = document.viewport.getScrollOffsets();
                
    var x =
        ((window.innerWidth ? window.innerWidth : document.documentElement.clientWidth) / 2) -
        (box.getWidth() / 2) +
        scroll.left;
        
    var y =            
        ((window.innerHeight ? window.innerHeight : document.documentElement.clientHeight) / 2) -
        (box.getHeight() / 2) +
        scroll.top;
    
    box.setStyle({ left: x + 'px', top: y + 'px' });    
    box.show();
}

function HideDiv(divName)
{
    $(divName).hide();
}

function ShowMessage(title, message)
{                            
    var header = $('header');
    var msg = $('message');                     
        
    header.innerHTML = title.toString();
    msg.innerHTML = message.toString();                                  
    
    OpenDivCenter('messageBox', true);
}

function CloseMessage()
{
    $('messageBox').hide();
    $('container').show();
}