* Hello, I'm writing a small threaded program in ruby and while it's running ok under c-ruby, when run under jruby, i'm getting

java.lang.ClassCastException: org.jruby.RubyNil cannot be cast to org.jruby.RubyMatchData

The code looks like this:

      
```
threads << Thread.new do
         segment_processor = FileSegmentProcessor.new(input)
         segment_processor.process do |line|
           yield line
         end
       end
```