function lastMod()
{
        var x = new Date (document.lastModified);
        Modif = new Date(x.toGMTString());
        Year = takeYear(Modif);
        Month = Modif.getMonth();
        Day = Modif.getDate();
        Mod = (Date.UTC(Year,Month,Day,0,0,0))/86400000;
        x = new Date();
        today = new Date(x.toGMTString());
        Year2 = takeYear(today);
        Month2 = today.getMonth();
        Day2 = today.getDate();
        now = (Date.UTC(Year2,Month2,Day2,0,0,0))/86400000;
        daysago = now - Mod;
        if (daysago < 0) return '';
        unit = 'days';
        if (daysago > 730)
        {
                daysago = Math.floor(daysago/365);
                unit = 'years';
        }
        else if (daysago > 60)
        {
                daysago = Math.floor(daysago/30);
                unit = 'months';
        }
        else if (daysago > 14)
        {
                daysago = Math.floor(daysago/7);
                unit = 'weeks'
        }
        var towrite = 'last modified ';
        if (daysago == 0) towrite += 'today';
        else if (daysago == 1) towrite += 'yesterday';
        else towrite += daysago + ' ' + unit + ' ago';
        return towrite;
}


function takeYear(theDate)
{
        x = theDate.getYear();
        var y = x % 100;
        y += (y < 38) ? 2000 : 1900;
        return y;
}