Deathcap not granting passive bonus?

I have noticed the item Rabadon's Deathcap now has an indicator telling you the bonus ap you receive as it's passive, which is awesome. I was super excited to see the bonus I was receiving (to help my laziness, I mean) so I could better gauge when to buy the deathcap in game.

However, letting curiosity get the better of me to see exactly how much ap I was getting from the bonus... The bonus keeps reading "0." This has now happened multiple times, both on summoner's rift and the howling abyss, and I thought at first maybe it was a visual glitch..? But then I actually looked at my ap, and unfortunately I am only getting the 120 from the active effect of the deathcap... and the ap drop on my full build for (this has happened on Diana, Katarina, Syndra, Orianna, and Heimerdinger, now) my ap carries between now and a few days ago is HIGHLY NOTICEABLE. D:

Is there any way currently to fix this, or am I the only one experiencing this, or...?

Ahah. Help please, anyone~

Moonmoon needs her ap