Need help with ActiveWarehouse-ETL-0.9.1 PG connection problem

I am trying to load conversion data into a postgresql database using
activewarehouse-etl. I can create a flat file output from the
conversion data without problem. However, when I try to load into the
table using the information contained in config/database.yml I see
this error:

/usr/lib64/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/
base.rb:1959:in `method_missing': undefined method
`postgresql_connection' for #<Class:0x2ad8c8e90428> (NoMethodError)

Can anyone hazard a guess as to what this means, what might be causing
it and how I might fix it? The only reference to
`postgresql_connection' that I can find in AR-2.3.5 is this:

# activerecord-2.3.5/lib/active_record/connection_adapters/
postgresql_adapter.rb

module ActiveRecord
  class Base
    # Establishes a connection to the database that's used by all
Active Record objects
    def self.postgresql_connection(config) # :nodoc:
      config = config.symbolize_keys
      host = config[:host]
      port = config[:port] || 5432
      username = config[:username].to_s if config[:username]
      password = config[:password].to_s if config[:password]
. . .