Hide Field Based On Group Membership

I have a number of fields that need to be hidden from members of some groups. I've had a look at the "security" module within ASPRunner 6.1 but it only allows permissions to be set per page, as opposed to on a per field basis.
So, for example, we have a product database containing two price fields. Our buying team need to be able to access both these fields, but one of these fields should be hidden from our sales team.
Is there a way within ASPRunner of hiding a field based on GroupID?
Thanks in anticipation.