title: AWS-SDK Rails 3.1 Ruby 1.9.3 Writes fail
body: <p>I can read from my amazon bucket, but write kept failing.</p>
  
  <pre><code>  s3 = AWS::S3.new
    bucket = s3.buckets['tmp']
    obj = bucket.objects["test.rtf"]
    obj.write(:file =&gt; "/Volumes/.../test.rtf")
  </code></pre>
  
  <p>It will Seg fault. No useful information is given to help me debug it. Any ideas? 
  I am using AWS-SDK gem, Rails 3.1.3, Ruby 1.9.3</p>