HotSpot asserts when running Queens with -XX:+TraceThreadEvents.

# Internal Error (/home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/mutex.cpp:1361), pid=28661, tid=139769043875584
# assert((!thread->is_Java_thread() || ((JavaThread *)thread)->thread_state() == _thread_in_vm) || rank() == Mutex::special) failed: wrong thread state for using locks

#4 0x00007f8c13dafd95 in report_vm_error (file=0x7f8c144d7cd0 "/home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/mutex.cpp", line=1361,
    error_msg=0x7f8c144d7f60 "assert((!thread->is_Java_thread() || ((JavaThread *)thread)->thread_state() == _thread_in_vm) || rank() == Mutex::special) failed",
    detail_msg=0x7f8c144d7f38 "wrong thread state for using locks") at /home/stefank/hg/hsx-gc-clean/src/share/vm/utilities/debug.cpp:220
#5 0x00007f8c14120782 in Monitor::check_prelock_state (this=0x1423ea8, thread=0x150a000) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/mutex.cpp:1360
#6 0x00007f8c14122151 in Monitor::lock (this=0x1423ea8, Self=0x150a000) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/mutex.cpp:894
#7 0x00007f8c14122393 in Monitor::lock (this=0x1423ea8) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/mutex.cpp:935
#8 0x00007f8c1429f5b4 in Thread::trace (msg=0x7f8c1454d350 "is_interrupted", thread=0x150a000) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/thread.cpp:378
#9 0x00007f8c1429f686 in Thread::is_interrupted (thread=0x150a000, clear_interrupted=false) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/thread.cpp:764
#10 0x00007f8c1414b972 in ObjectMonitor::wait (this=0x1510878, millis=0, interruptible=true, __the_thread__=0x150a000) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/objectMonitor.cpp:1502
#11 0x00007f8c14267baf in ObjectSynchronizer::wait (obj=..., millis=0, __the_thread__=0x150a000) at /home/stefank/hg/hsx-gc-clean/src/share/vm/runtime/synchronizer.cpp:388
#12 0x00007f8c13fbcdea in JVM_MonitorWait (env=0x150a200, handle=0x7f8c0d2605c8, ms=0) at /home/stefank/hg/hsx-gc-clean/src/share/vm/prims/jvm.cpp:525

(gdb) p thread->is_Java_thread()
$5 = true
(gdb) p ((JavaThread*)thread)->thread_state()
$6 = _thread_blocked
(gdb) p (lock_types)this->rank()
$7 = Monitor::barrier