Glitch with "banish" as item ability

I've created an item, which has the active ability to cast 'banish'. It works fine but when i banish a unit, my hero and any other units are able to attack the banished one. That's not the case when using the standard ability of the bloodmage (which i have in fact only copied and made it an 'item ability'). I tried to fix this bug by using a casting dummy instead (also the bloodmage himself, just for testing) but it doesn't help anyway :(
Does someone have an idea how to change/fix this glitch?

What's the damage type of your units? if it's an magic attack then they can attack of course a banished unit, the same also counts for etheral units. (To my knowledge)
I personally never had any problems with banish / etheral.

Omg, no, all units have different damage types... piercing, hero, normal ...

€dit: Ok, i have tested some things and have noticed something strange: At my map, the standard banish of the bloodmage also doesn't work !! ahh, are there any global settings which could be responsable for this banish glitch?!?!

You're sure the banish is going through - you're not interrupting it with a trigger of some kind?

Yeah, the banish itself works fine, you can see the buff and effect and so on.
But the unit doesn't seemed to count as etheral.

€dit: Oh, i found the bug: the gameplay constant 'Drain uses etheral bonus' has to false, otherwise, banished units aren't etheral O.o ... very strange, veeeery strange....

Well I'm pretty sure that wasn't causing the bug as all that constant does is determine whether or not the spell drain does extra damage to ethereal units, but if the ability is working for you now, congratulations.

You changed armor/damage constants in your map.

For banish to work in standard way all attack types except magic must deal zero percent to ethereal units.

You changed that and banish stopped working normally.

I'm sure that I only reseted the named value, nothing more. How I sayed: very strange O.o
@cohadar: that was my first thought too, but i have had already the standard setting for this value...