What exactly happens on your box? Is there a specific kind of exception raised? I tested this on a CentOS 5.x box with Ruby 1.8.5 and seems to work:

    $ /usr/bin/irb
    irb(main):001:0> RUBY_VERSION
    => "1.8.5"
    irb(main):002:0> ('0'..'9').to_a.join
    => "0123456789"
    irb(main):003:0>

I am not averse to applying the patch if we can get a more concrete idea of exactly how it's failing on your machine, although it looks like you removed line 294 as well by mistake, so that would need to be corrected.