Problem with pthread_kill, maybe bug?

Hi!

I compiled ngpt-2.0.1 yesterday and tried to make mysqld use it.

It starts fine and answers request but when you try to stop it (via
network command or kill), it hangs.

After some debugging I found the following:

The main thread does a select() to wait for new incoming connections
which are then handled by separate threads.

When the server is stopped, the function for shutdown is called and it
tries to pthread_kill(main_thread, SIGUSR1) which should obviously cause
the main thread to abort waiting in select() but which it doesn't. A
quick check with LinuxThreads showed that it did it there.

I'm not sure if it's mysql's fault (not correctly setting up signals or
something), but mysql is supposed to work with other pthread
implementations than only LinuxThreads, so I ask if this might be a bug.