Hi Kihwal, there are two classes, org.apache.hadoop.mapreduce.TestSleepJob and org.apache.hadoop.mapred.gridmix.TestSleepJob, which TestSleepJob are you referring to?
For org.apache.hadoop.mapreduce.TestSleepJob, it was not committed to 0.20s until rev 1169585 according to the svn log. It was neither in rev 1167444 nor rev 1167663. So it could not be failed in these revisions. BTW, it is a mapreduce test program but not a unit test.
For org.apache.hadoop.mapred.gridmix.TestSleepJob, I ran it and it did not fail.