Bug at /damage command: Unresolved references

If you take as damage type e.g. "arrow" and die because of this, the death notice says "%1$s was shot by &2$s". This happens always when two entities would be present in the real game (e.g. Player and skeleton): If I select "indirect_magic" as damage type, the death notice says "%1$s was killed by &2$s using magic".