Merge pull request #1761 from CJentzsch/patch-3

fix block time issue
(cherry picked from commit e98854588b)

miner/worker.go

@@ -431,7 +431,7 @@ func (self *worker) commitNewWork() {
 	tstart := time.Now()
 	parent := self.chain.CurrentBlock()
 	tstamp := tstart.Unix()
-	if parent.Time().Cmp(new(big.Int).SetInt64(tstamp)) != 1 {
+	if parent.Time().Cmp(new(big.Int).SetInt64(tstamp)) >= 0 {
 		tstamp = parent.Time().Int64() + 1
 	}
 	// this will ensure we're not going off too far in the future