[Solved]-Highcharts (javascript) strange artifact (bug?) with simple graphic-Highcharts

this is because your series is not sorted by time. you have the following:

...
[date.utc(2014, 02, 7, 13, 14), 1351],
[date.utc(2014, 02, 7, 14, 03), 6391],
[date.utc(2014, 02, 7, 20, 02), 5231],
[date.utc(2014, 02, 7, 16, 28), 837],
[date.utc(2014, 02, 7, 17, 00), 541],
...

sort all your data with ascending time scale.