Is there a workaround to getting AWS::S3 working on macruby?

This works when I try it in MRI. But this is what happens in Macruby:

$ macirb -f
irb(main):003:0> require 'aws/s3'
=> true
irb(main):006:0> AWS::S3::Base.establish_connection!(
irb(main):007:0> :access_key_id     => ACCESS_KEY,
irb(main):008:0> :secret_access_key => SECRET_ACCESS_KEY
irb(main):009:0> )
=> #<AWS::S3::Connection:0x40043ed60 @options={:server=>"s3.amazonaws.com", :port=>80, :access_key_id=>"XXXX", :secret_access_key=>"XXXX"} @access_key_id="XXXX" @secret_access_key="XXXX" @http=#<Net::HTTP s3.amazonaws.com:80 open=false>>
irb(main):010:0> AWS::S3::Service.buckets
NameError: `@policy:' is not allowed as an instance variable name
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:142:in `expirable_memoize:'
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:176:in `policy:'
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/开发者_Go百科s3/response.rb:84:in `empty?'
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/s3/service.rb:22:in `unmemoized_buckets_1314299902'
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:177:in `block'
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:146:in `expirable_memoize:'
    /Users/jeremysmith/.rvm/gems/macruby-0.10/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:176:in `buckets'

It looks like it doesn't like the : in @policy. You could hack the AWS gem to replace all occurrences of @policy: with @policy and see if that fixes the problem.