Contract Vether4 function _recordBurn does not check that _eth > 0, thus it is possible to pass this check multiple times:
if (mapEraDay_MemberUnits[_era][_day][_member] == 0)
If the user hasnt contributed to this day yet, it updates mapMemberEra_Days, mapEraDay_MemberCount, and mapEraDay_Members. However, when msg.value is 0, it is possible to trigger this condition again and again as mapEraDay_MemberUnits still remains 0.
Recommend either not allowing burns of 0 _eth, or add an extra check in the if statement.
