Cucumber segfaults

Just started getting this, every time I run rake features:

myapp/vendor/rails/actionpack/lib/action_controller/vendor/rack-1.0/
rack/lint.rb:16: [BUG] Segmentation fault
ruby 1.8.6 (2008-03-03) [i686-darwin9.2.2]

after updating from cucumber 0.3.0 to 0.3.2 I’m now getting the
segfault here:

myapp/vendor/gems/nokogiri-1.2.3/lib/nokogiri/xml/node_set.rb:138:
[BUG] Segmentation fault
ruby 1.8.6 (2008-03-03) [i686-darwin9.2.2]

While trying to ascertain a cause, I discovered something weird.
It seems to be related to the number of scenarios I’m running.
I had 11 scenarios, and I was getting the error every time.
I tried to isolate a cause, but the bug would not happen for any
individual scenario. I thought maybe there’s some combination effect,
so I started grouping them.
I can get the error to happen about 50% of the time if I have 3 or 4
scenarios (10-12 steps)
It happens 100% of the time with more than 6 scenarios.
It happens 0% with any of the individual scenarios.

any ideas how to debug this?