Necromantic Rune not working?

[KeeseroGu]

     I just recently dinged 28 and got my replace for the utterly useless Summoner's Mark, I'm sure it's a bit more useful to conjurors. Either way before 28 I had kept Summoner's Mark on my pet for the heck of it and I remember seeing the icon for exposed elements pop up in my spells window fairly often. However, since I've started using Necromantic Rune I have not yet seen it proc Exposed Noxious during any of the forty some mobs I've killed since then. Seeing as the rate is somewhere around 20% I figured this isn't working as it should, is this a known problem, or am I missing something? <div></div>

[Xalmat]

Check your chat logs. If it's working properly, you'll see a spell emote like you would with Summoner's Mark.