Hi,

Thank you very much for the quick response and the fix!

MRI 1.9 backtraces are now much closer to 1.8.6.

I've found one more difference, so maybe you could comment on it too?

It seems that send and __send__ method invocations do not produce the
frame visible in the stacktrace anymore.

"hello".__send__(:sub, /l/, 5)

In 1.8.6:
stacktrace.rb:13:in `sub': can't convert Fixnum into String (TypeError)
        from stacktrace.rb:13:in `__send__'
        from stacktrace.rb:13

In 1.9:
stacktrace.rb:13:in `sub': can't convert Fixnum into String (TypeError)
        from stacktrace.rb:13:in `<main>'

Thanks,
  --Vladimir