// Usage: checkSelection(document.formname,'checkboxprefix',action)
// action can be: 0|none , 1|all , -1|inverse
function checkSelection(formObj, prefix, action)
{
    for (var i=0;i < formObj.length;i++) 
    {
        elem = formObj.elements[i];
        if (elem.type == 'checkbox' && elem.name.indexOf(prefix) == 0)
        { 
            if (action == 0 || action == 'none')
            {
                elem.checked = false;
            }
            else if ( action == 1 || action == 'all')
            {
                elem.checked = true;
            }
            else
            {
                elem.checked = (elem.checked) ? false : true;
            }
        }
    }
}

// Opens URL openURL in a new window with name windowName
function openWindow(openURL, windowName) {
    if (!windowName) { windowName = 'mydefault' }
    win = window.open(openURL,windowName);
    win.focus ();
}