PROBLEM:  (QAR 69251)    (Patch ID: OSF440-054)
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In the latest development version (version 52), Ladebug has has begun to
employ a "user thread hold" mechanism.  The initial testing of this mechanism
has revealed bugs in DECthreads code bases which might result in missed
breakpoints and watchpoints, as well as causing application hangs.

PROBLEM:  (CLD HPAQ21HQ9)    (Patch ID: OSF440-054)
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Customer was encountering an invalid scheduling priority bugcheck, which
appears to be caused by incorrect referencing of scheduling data structures
inside DECthreads.

PROBLEM:  (QAR 69364)    (Patch ID: OSF440-054)
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The manager thread is being scheduled to run in response to a system event
(nxm action, timer queue expiration, etc) but is not recognizing the event
as the reason it was scheduled to run.
  
The manager thread then goes back to sleep, only to wake up again in response
to the still unserviced system event.  An infinite loop results.

PROBLEM:  (72100, 74961, 75971) (PATCH ID:)
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Threaded applications which make extensive use of synchronization objects
(mutexes, condition variables) may encounter performance and scaling
regressions when run on an EV6 SMP machine.  Customers encountering these
regressions may observe negative scaling, decreased application throughput
and increased CPU utilitzation, as the number of EV6 CPUs is increased.
This version of DECthreads contains changes to the implementation of
synchronization objects and thread scheduling around those objects to
improve performance on EV6 SMP.  No functional or interface changes were
made.