utest failed: DistributionSequenceTest.setSeed() and simpleSequence()

$ ant stress-test -Dtest.name=DistributionSequenceTest

stress-test:
    [junit] Testsuite: org.apache.cassandra.stress.generate.DistributionSequenceTest
    [junit] Testsuite: org.apache.cassandra.stress.generate.DistributionSequenceTest Tests run: 4, Failures: 2, Errors: 0, Skipped: 0, Time elapsed: 0.08 sec
    [junit]
    [junit] Testcase: simpleSequence(org.apache.cassandra.stress.generate.DistributionSequenceTest):    FAILED
    [junit] expected:<5> but was:<4>
    [junit] junit.framework.AssertionFailedError: expected:<5> but was:<4>
    [junit]     at org.apache.cassandra.stress.generate.DistributionSequenceTest.simpleSequence(DistributionSequenceTest.java:37)
    [junit]
    [junit]
    [junit] Testcase: setSeed(org.apache.cassandra.stress.generate.DistributionSequenceTest):   FAILED
    [junit] expected:<5> but was:<4>
    [junit] junit.framework.AssertionFailedError: expected:<5> but was:<4>
    [junit]     at org.apache.cassandra.stress.generate.DistributionSequenceTest.setSeed(DistributionSequenceTest.java:111)
    [junit]
    [junit]
    [junit] Test org.apache.cassandra.stress.generate.DistributionSequenceTest FAILED