Item/spell with same base ability won't go in cooldown

I made a little trick to allow a unit have the same ability two times - as a normal ability and as an ability given through an item. The point is that a unit can cast a spell (Blizzard, for example) through his item and through the normal ability. The problem is that when I cast the item, the normal ability does NOT go in cooldown but the item does. Same is with the reverse effect (first normal, then item). Yes, I have checked the item to be in the same cooldown group but it still doesn't work. Making the spell an item ability gives the same result.

EDIT: I forgot to mention that when the item is acquired, the unit receives the extra ability. Normally this cannot happen because the item ability would override the normal and the normal won't show at all. That's why I have to add the ability in the Object Editor and disable it at map start and when the unit gets a specific item, I enable a specific ability - bam it works, except the cooldown part.

Bumpy? I really need this one ...

Make one version of the ability a dummy version with a triggered cast of the actual spell?

Use Channel and trigger the rest.

> Use Channel and trigger the rest.
How the hell am I going to make the spell go in cooldown? ^^

> Make one version of the ability a dummy version with a triggered cast of the actual spell?
Like, how? The ability is the same - it is just one. I was just able to make it to be used by the item and from a normal cast with hotkey... As I said, the problem comes from the fact that only one of them goes in cooldown.

You cannot share the cooldown of an item with a regular ability. It's just impossible.

> It's just impossible.
You just broke my dreams... Thanks anyway.

EDIT: Actually, it is possible. Found a way ^^