the fields for 2.6.6 are
'id' => 'int(11) UNSIGNED NOT NULL AUTO_INCREMENT',
'virtuemart_order_id' => 'int(1) UNSIGNED',
'order_number' => 'char(64)',
'virtuemart_paymentmethod_id' => 'mediumint(1) UNSIGNED',
'payment_name' => 'varchar(1000)',
'payment_order_total' => 'decimal(15,5) NOT NULL',
'payment_currency' => 'smallint(1)',
'email_currency' => 'smallint(1)',
'cost_per_transaction' => 'decimal(10,2)',
'cost_percent_total' => 'decimal(10,2)',
'tax_id' => 'smallint(1)',
'sofort_custom' => 'varchar(255)',
'security' => 'varchar(50)',
'sofort_response_amount' => 'decimal(15,5) NOT NULL',
'sofort_response_currency' => 'varchar(50)',
'sofort_response_status' => 'varchar(50)',
'sofort_response_status_reason' => 'varchar(50)',
'sofort_response_transaction' => 'varchar(100)',
'sofort_response_invoice' => 'varchar(1000)'
don't know if u speak German but found this on the German VM forum
http://forum.virtuemart.de/installation-updates-einrichtung-156/fehlermeldung-0401-a-1308/