Patch for acts_as_list plugin to select only the necessary column

Hello,

I'm not sure who is responsible for the now spun off acts_as_list
plugin.

The acts_as_list plugin only needs to know the value of the
position_column in many cases, but it is loading the entire row. It
doesn't seem like efficient behaviour to me. Would any one mind taking
a look at http://dev.rubyonrails.org/ticket/11240 where I have tried
to fix this?

This is my first attempt at reporting a rails 'bug' and creating a
patch.

Thanks,

- Paul