Unable to socket Vitality into Malice skill from Sceptre

Vitality: Supports Persistent Buff skills
Malice: Persistent Buff skill

Attempting to socket Vitality into Malice: "Warning: This support can't be socketed into this skill."

I suspect its related to the reduced attribute req. modifier on this specific sceptre which lets me equip at less than 30 strength. The str req. for malice remains listed at 30 on the skill screen, but I do still appear to at least have the buff aura visibly on my character.