priorities of newly-created threads

Hi,

In Ruby 1.8 a newly created thread has the priority of the thread that 
created it.

In Ruby 1.9, newly created threads start at priority 0.  I suspect that 
this is a bug.

Here's my test code:

t1 = Thread.new {
   Thread.current.priority = -1

   t2 = Thread.new {
     puts "child thread priority: #{Thread.current.priority}"
   }
   t2.join
}
t1.join

And here's the output:

$ ruby -v priority.rb
ruby 1.8.6 (2007-03-13 patchlevel 0) [i686-linux]
child thread priority: -1

$ ruby1.9 -v priority.rb
ruby 1.9.0 (2007-08-09 patchlevel 0) [i686-linux]
child thread priority: 0