The cleric prayer Servitude in Death has as its effect
The first time the target dies before the end of the encounter, it rises at the start of its next turn as an undead creature allied with you and your allies. Until it dies again, the creature is dominated by you. It has 1 hit point…. (Heroes of Shadow 83 and emphasis mine)
The feat Unnatural Mantle says
While you have at least 1 power point, allies within the area of your Ardent Mantle remain conscious when dropped to 0 or fewer hit points until they roll their first death saving throw. (Dragon #389 31 and emphasis mine)
Does the Unnatural Mantle feat interact with undead creature that rises as the result of the Servitude in Death prayer when that servitor is reduced to 0 hp?