Segmentation fault

When I require the file thusly:

``` ruby
require File.dirname(__FILE__) + "/lighthouse-api/lib/lighthouse"
```

I get:

``` shell
~/.rvm/gems/ruby-1.9.2-p180/gems/json-1.5.3/ext/json/ext/json/ext/parser.bundle: [BUG] Segmentation fault
ruby 1.8.7 (2009-06-12 patchlevel 174) [universal-darwin10.0]
```

I also tried gem install with a simple require and got the same result.  Help please?  
