def hi
  sleep 2
  hello
end

def hello
  raise "hi"
end

th = Thread.new do
  hi
end

th.join

# ruby 1.9.3
# /tmp/a.rb:7:in `hello': hi (RuntimeError)
#        from /tmp/a.rb:3:in `hi'
#        from /tmp/a.rb:11:in `block in <main>'
# ruby 1.8.7
# /tmp/a.rb:7:in `hello': hi (RuntimeError)
#        from /tmp/a.rb:14:in `join'
#        from /tmp/a.rb:14