AbleCommerce Shopping Cart Software

Given that accessing user-defined data through DataPort seems to be impossible (well, there are no replies to my post!), how should the VAT number for a user be stored, so that it is export-able with DataPort??

User table contains a Comment field that is not used by AbleCommerce any where. One way is to put your VAT number in Comment field for user and CSV export will take care of it.