Agentry 7.x in Andorid - Update rule not updating when return value is blank?

Hi,

I have an update rule that in certain condition must return the global Application.Blank to update a transaction screen field.

But the field is not being updated when the return value is blank. If I change the global for Application.Dash, then it is correctly updated, but I need to have an empty string, not a dash.

Any clue about why this is happening?

Thank you,

Marçal