irb(main):001:0> a = true
=> true
irb(main):002:0> fork do
irb(main):003:1* a = false
irb(main):004:1> end
=> 2525
irb(main):005:0> a
=> true


Why is this so?  What is the point of having my mutexes if I can't
manipulate the data anyway?

-Kurt