[Forums] Select2 mandatory validation fails for ListBox

Select2 is placed on ListBox.
The field has manadatory set to true
Special List:
Value 1: 0
Option 1: -

Validation on submit button: Client & Server

When the user does not select a value (so - is choosen in the listbox) the form can be submitted.
The error "Required field!" should have be shown instead and the form should not be submitted.

Note: when select2 is not applied to the listBox (so you get the normal listBox) it works fine.