var window_handle;
var window_page; 

function openMain(page) {
    if (opener) opener.location.href = page;
    else {
        window.open();
        window_page = page;
        setTimeout('reopen_opener()',100);
    }
    return false;
}

function reopen_opener() {
    opener = window.open(window_page,'main');
    opener.window_handle = self;
    opener.window_handle.closed = false;
}