Activemerchant and UK Maestro (formerly Switch) problem

Hi,

I am having problem with users reporting malfunctioning of UK Maestro cards functionality on website of a client. I am using most recent Activemerchant library from github, which I managed to make work with rails 1.2.

Reported error is:

Credit card invalid: start_month is invalid issue_number cannot be empty.

In my code I made special case for UK Maestro:

       credit_card = ActiveMerchant::Billing::CreditCard.new(            :type => params[:payment][:card_type],            :number => params[:payment][:card_number],            :month => params[:payment][:card_valid_ex_month],            :year => params[:payment][:card_valid_ex_year],            :first_name => @join_request.first_name,            :last_name => @join_request.last_name,            :verification_value => params[:payment][:security_number]        )

     start_month = params[:payment][:card_valid_from_month]      start_year = params[:payment][:card_valid_from_year]      issue_number = params[:payment][:issue_number]

     if params[:payment][:card_type] == "switch"        credit_card.start_month = start_month if start_month and start_month != ""        credit_card.start_year = start_year if start_year and start_year !=""        credit_card.issue_number = issue_number if issue_number and issue_number != ""      end

     ... do rest of processing ...

I am using: Rails 1.2 + patched activesupport to work with activemerchant Activemerchant 1.3.2

Please for any suggestion on what I am doing wrong or piece of code that is proven to work with old UK Maestro/Switch cards.

Thanks, H.