Suppress #ERR if cell is empty

Hi,
I am using AW.Formats.Date for some columns with date values:

var dateLong = new AW.Formats.Date;
dateLong.setDataFormat("ISO8601");
dateLong.setTextFormat("mm-dd-yyyy");

If a cell is empty (e.g. the end date is not set) I get an #ERR instead of an empty cell.

Can I suppress this?

Thanks in advance.

OK, I found something that seems to work for me:

date.setErrorText("");
date.setErrorValue(0);