System.currentTimeMillis() not accurate on Windows ?

Hi,
JVM : 1.4.2_03-b02
OS : Windows XP
processor : XEON 2.4 GHz
Following test fails with 62.5 error percentage.
Is it due to windows failing to give time on a millisecond level ?
Or is there another reason ?
public void testSleep() throws Exception {
    int total = 1000;
    int errors = 0;
    for ( int j = 0; j < total; j++ ) {
      long start = System.currentTimeMillis();
      Thread.sleep(5);
      long end = System.currentTimeMillis();
      if ( end < start+5 ) {
        errors++;
    Float errorPercentage = new Float( errors*(float)100/total );
    assertEquals( new Float(0), errorPercentage );
}Regards, Tom.

The millisecond level of precision is only a possibility provided by the API, the OS does not forcibly provide it.
But Thread.sleep will not be absolutely precise, it is the most likely culprit.

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