NOT updating fax fields...

Is it possible to selectively not update certain fields with Plaxo, such as the fax field in Outlook? Fax numbers, as many know already, are treated the same as email addresses by Outlook, which is very troublesome and I've already read several posts on the subject but none on this question. This would also seem to be the better than any workaround with third party software or manipulating contacts through copying or exporting, etc.

Thanks.