Segmentation fault with Ruby 1.8.7

Question

I'm trying to use Rails 3.2.0.rc2 but I'm running into some problems. When I try to do a rails s I am now getting:

/Users/Kyle/.rvm/gems/ruby-1.9.2-p290@skateparks/gems/json-1.6.5/ext/json/ext/json/ext/parser.bundle: [BUG] Segmentation fault
ruby 1.8.7 (2010-01-10 patchlevel 249) [universal-darwin11.0]

[1]    28744 abort      rails s

What's interesting is that I am using 1.9.2 but the error seems to be related to 1.8.7. I have done the following to try to fix this problem w/ no success:

rvm gemset empty
rvm use 1.9.2@skateparks
gem install bundler
bundle install