Currently it is not possible in Data Generator Wizard, to generate list of random IBAN (bank account) numbers. Since IBAN Bank account numbers can have different lengths (15 to 30 characters),...
Actually, I have found an online service which can create Dutch and international IBAN numbers.
It's on:
http://www.mobilefish.com/services/bankaccount_bsn_numbers/bankaccount_bsn_numbers.php