[ActiveRecord] new connector implementation gives 'unknown attribute error'

Hi all,
I'm implementing an activerecord connector on top of a database driver
I wrote (in pure ruby).

The platform of reference is a Mac OSX 10.5 box with the shipped ruby
interpreter version 1.8.6 and activerecord 2.3.2.

Table creation and select queries work; I though have some problems
when I try to perform insertion.

As an example I created a table called 'albums':

ActiveRecord::Schema.define do
    create_table :albums do |table|
        table.column :title, :string
        table.column :performer, :string

class Album < ActiveRecord::Base

Manual insertion works: