fluentdのretry処理時刻が過去になっている

gistfile1.txt

# stacktrace

 2013-02-12 04:38:39 +0900: failed to communicate hdfs cluster, path: ...
 2013-02-12 04:38:39 +0900: temporarily failed to flush the buffer, next retry will be at 2013-02-12 04:37:10 +0900. error="{...
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/webhdfs-0.5.1/lib/webhdfs/client_v1.rb:278:in `request'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/webhdfs-0.5.1/lib/webhdfs/client_v1.rb:232:in `operate_requests'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/webhdfs-0.5.1/lib/webhdfs/client_v1.rb:46:in `append'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/fluent-plugin-webhdfs-0.1.0/lib/fluent/plugin/out_webhdfs.rb:100:in `send_data'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/fluent-plugin-webhdfs-0.1.0/lib/fluent/plugin/out_webhdfs.rb:109:in `write'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/fluentd-0.10.30/lib/fluent/buffer.rb:279:in `write_chunk'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/fluentd-0.10.30/lib/fluent/buffer.rb:263:in `pop'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/fluentd-0.10.30/lib/fluent/output.rb:303:in `try_flush'
  2013-02-12 04:38:39 +0900: /usr/local/lib/ruby/gems/1.9.1/gems/fluentd-0.10.30/lib/fluent/output.rb:120:in `run'
 
 
 # fluentd.conf
 
  <store>
    type webhdfs
    host ...
    port ...
    username ...
    path ...

    field_separator TAB        # or 'SPACE', 'COMMA'
    output_include_time false
    output_include_tag false
    output_data_type attr:log
  
    # default val. is 60 on 'BufferedOutput'
    flush_interval 1
    # default val. is 8*1024*1024 on 'BasicBuffer'
    # default val. is 256*1024*1024 on 'TimeSlicedOutput'
    buffer_chunk_limit 128M
    # default val. is 256 on 'BasicBuffer'
    buffer_queue_limit 32
  </store>