damage from damage mechanic can't be checked by damagecause conditions

onDamaged aura and trigger can't use damagecause condition to check and cancelEvent the damage if damage is from mms' damage mechanic. (vanilla damage work fine) I already tested with many type of damagecause, so this bug is either from damagecause condition or damage mechanic.

how to reproduce:

1. /mm t cast block
2. /mm t cast testdamage

block:
  Skills:
  - onDamaged{auraName=blocking;d=200;cE=true;oH=blocked-target} @Self
 
 
blocked-target:
  Conditions:
  - damagecause{cause=ENTITY_ATTACK} true
  Skills:
  - message{m="<trigger.name>"} @Self
 
testdamage:
  Skills:
  - damage{a="100"} @Self{targetSelf=true}