rails2和aws simple(simpledb):不能从amazon simpledb中删除数据?

我正在aws sdb(0.3.1)版本中使用aws sdb gem http://developer.amazonwebservices.com/connect/entry.jspa?externalID=1242

>> t=Team.find(:first)
=> #<Team:0x329f718 @prefix_options={}, @attributes={"updated_at"=>Fri May 28 16:33:17 UTC 2010, "id"=>0}>
>> t.destroy
=> #<Net::HTTPOK 200 OK  readbody=true>
>> t=Team.find(:first)
=> #<Team:0x321ad38 @prefix_options={}, @attributes={"updated_at"=>Fri May 28 16:33:17 UTC 2010, "id"=>0}>

根据上述教程,团队模型是一个普通的ActiveResource模型。

   class Team < ActiveResource::Base
     self.site   = "http://localhost:8888" # Proxy host + port
     self.prefix = "/fb2010_dev/"       # SDB domain
   end