I'm getting a different error with x86_64, but probably not protected against other bugs:
(irb):3:in `[]=': failed to allocate memory (NoMemoryError)
from (irb):3:in `irb_binding'
from /usr/lib/ruby/1.8/irb/workspace.rb:52:in `irb_binding'
from /usr/lib/ruby/1.8/irb/workspace.rb:52
(irb):3:in `[]=': failed to allocate memory (NoMemoryError) from (irb):3:in `irb_binding' from /usr/lib/ruby/1.8/irb/workspace.rb:52:in `irb_binding' from /usr/lib/ruby/1.8/irb/workspace.rb:52