Damage Over Time and Item Rarity on Equipment

Hi everyone,

I have played now several DOT Builds in Endgame (Poison, Ignite, Bleed) and I was wondering if Item Rarity on Items is working.

Two Questions now:
1) Is Item Rarity on Equipment working on DOT builds in which the DOT is killing the enemy?

2) The more important Question: If the answer is "No, only on on-Hit-Effect": Is this intended or just a bug, which will be fixed?

Thanks