Equations in QTY colum of Solidworks BOM not retained when saved

I have a problem whereby I am inserting an equation into theQTY column of a Solidworks 2008 BOM to display an error message ifthe qty is zero (for virtual components defined by a custom qtycustom property). This works great until I try to save the BOM as atemplate. Once I try to reuse the template on a new drawing, theequation is gone. This does not happen on any other column, exceptfor thr QTy column.

Anyone know if this is by design or a bug?

Thanks,

OliverSolidworksBill Of Materials