fields_for and field ordering

[Chris Booth]

I'm trying to use the shiny new fields_for (in Rails 2.3.2) to display
some custom fields for a form. I want these fields to be ordered by a
field_order field that is in the model. However, it appears that
fields_for is always ordering by the updated_at field. What that
means is that if the user fills in some of the fields, and then clicks
my "edit" link to go back and edit the form, the fields reorder
themselves. I can't figure out a way that I can specify the order in
which the fields show up on the form with fields_for.

Does anyone have any insight on this?

Thanks,

Chris