by pkorotkov:

What steps will reproduce the problem?
This code does not work in Go Playground as-is, so just put it right there:

// DatesDiff returns the number of days and seconds resp. between two given dates
func DatesDiff(t1, t2 time.Time) (int, int64) {
    v := int64(t2.Sub(t1))
    return int(v / 864e11), v / 1e9
}

func main() {
    loc, err := time.LoadLocation("Europe/Berlin")
    if err != nil {
        fmt.Println(err.Error())
        return
    }
    t1 := time.Date(1957, time.September, 10, 0, 0, 0, 0, loc)
    t2 := time.Date(2013, time.May, 14, 0, 0, 0, 0, loc)
    fmt.Println(DatesDiff(t1, t2))
    t3 := time.Date(1957, time.September, 10, 0, 0, 0, 0, time.UTC)
    t4 := time.Date(2013, time.May, 14, 0, 0, 0, 0, time.UTC)
    fmt.Println(DatesDiff(t3, t4))
}

What is the expected output?

20335 1756944000

20335 1756944000

What do you see instead?
20334 1756940400

20335 1756944000

Which compiler are you using (5g, 6g, 8g, gccgo)?
8g

Which operating system are you using?
Windows 7 Prof x86
Ubuntu Linux 12.04 LTS x86

Which version are you using?  (run 'go version')
go version go1.0.1

Please provide any additional information below.