OldMBeanServerTest.java fail with 'AssertionError'

The test javax/management/MBeanServer/OldMBeanServerTest.java failed on Solaris-sparc in PIT JDK9_b08 with the incredibly useful error message 'java.lang.Exception: TEST FAILED: testBasic: got exception java.lang.AssertionError'

The log shows
java.lang.AssertionError
at OldMBeanServerTest$CountListener.waitForCount(OldMBeanServerTest.java:283)
at OldMBeanServerTest.testBasic(OldMBeanServerTest.java:297)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:484)
at OldMBeanServerTest.runTests(OldMBeanServerTest.java:185)
at OldMBeanServerTest.main(OldMBeanServerTest.java:138)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:484)
at com.sun.javatest.regtest.MainWrapper$MainThread.run(MainWrapper.java:94)
at java.lang.Thread.run(Thread.java:744)

RULE javax/management/MBeanServer/OldMBeanServerTest.java Exception java.lang.AssertionError