Custom section with scalable fields

Hi,

I would like to create a work item where I can define a set of attributes belonging  to a section (or subsection) which can be multiplied inside of the workitem... kind of a (+) button for a new line. I hope I made myself understood...

example: I want to put information into a workitem from a xls file... but sometime my excel file has 3 lines sometime has 5 or 6 or 7... I don't want to create a new workitem for each xls line.

Is this possible or presented as an enhancement in the future?