function DefaultButton(e, button)
{
    if (window.event) e = window.event;
    
    if ((e.which == 13) || (e.keyCode == 13)) 
    {
        var btn = document.getElementById(button);
        if (btn.tagName == "A")
        {
            document.location.href = btn.href;
        }
        else
        {
            btn.click();
        }
        
        return false;
    }
    else 
    {
        return true;
    }
}

// Allows only numbers to be entered
function DigitsOnly(e)
{
    var keynum;
    if(window.event) // IE
    {
      keynum = e.keyCode;
    }
    else if(e.which) // Netscape/Firefox/Opera
    {
      keynum = e.which;
    }
    return((keynum>=48&&keynum<=57) || (keynum==8)) // 8:"BackSpace"
}

// Allows only chars to be entered
function CharsOnly(e)
{
    var keynum;
    if(window.event) // IE
    {
      keynum = e.keyCode;
    }
    else if(e.which) // Netscape/Firefox/Opera
    {
      keynum = e.which;
    }
    return !(keynum>=48&&keynum<=57);
}