def sort=(value)
      if value.is_a? Hash
        value.assert_valid_keys(:sql, :method)
        @sort = value
      else
        @sort = value ? true : false # force true or false
      end
    end
def sort=(value)
      if value.is_a? Hash
        value.assert_valid_keys(:sql, :method)
        @sort = value
      else
        @sort = value ? true : false # force true or false
      end
    end
sorting on a column can be configured four ways:
   sort = true               default, uses intelligent sorting sql default
   sort = false              sometimes sorting doesn't make sense
   sort = {:sql => ""}       define your own sql for sorting. this should be result in a sortable value in SQL. ActiveScaffold will handle the ascending/descending.
   sort = {:method => ""}    define ruby-side code for sorting. this is SLOW with large recordsets!