Topic: Error with migrate for Oracle

(Sorry for the English)
I have :
Oracle 9.x
Rails 1.6

1)
I wont create table in oracle from migrate, but has error: ORA-00931
code of migration is symle:

class CreateOrders < ActiveRecord::Migration
  def self.up
    create_table :order, :schema => "RUBY" do |t|
       t.column :name, :string
    end
  end

  def self.down
    drop_table :order
  end
end


and run:

rake db:migrate

has error with tracer:
(in C:/ruby/imarket)
** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:migrate
** Invoke db:schema:dump (first_time)
** Invoke environment
** Execute db:schema:dump
rake aborted!
ORA-00931: missing identifier
(eval):3:in `__send__'
(eval):3:in `describe'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/connection_adapters/oracle_adapter.rb:361:in `columns'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/schema_dumper.rb:65:in `table'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/schema_dumper.rb:60:in `tables'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/schema_dumper.rb:51:in `each'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/schema_dumper.rb:51:in `tables'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/schema_dumper.rb:20:in `dump'
c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/schema_dumper.rb:14:in `dump'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/tasks/databases.rake:24
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/tasks/databases.rake:23:in `open'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/tasks/databases.rake:23
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/tasks/databases.rake:21:in `call'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:387:in `execute'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:387:in `each'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:387:in `execute'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:357:in `invoke'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:350:in `synchronize'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:350:in `invoke'
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/tasks/databases.rake:5
c:/ruby/lib/ruby/gems/1.8/gems/rails-1.1.6/lib/tasks/databases.rake:3:in `call'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:387:in `execute'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:387:in `each'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:387:in `execute'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:357:in `invoke'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:350:in `synchronize'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:350:in `invoke'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:1906:in `run'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:1906:in `each'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/lib/rake.rb:1906:in `run'
c:/ruby/lib/ruby/gems/1.8/gems/rake-0.7.1/bin/rake:7
c:/ruby/bin/rake:18:in `load'
c:/ruby/bin/rake:18

2)
when I wont create table for oracle a have to define scheme?
right code: CREATE TABLE "SCHEME_NAME"."TABLE_NAME"(..);
wrong code: CREATE TABLE "TABLE_NAME"(..);
whot I must do for detect scheme?

Help please!
Thank you