HI,
I had the same issue before, but it was with 5k switch, you shouldnt plug 4400 LAG with 5k switch, becuase simply the default load balancing algorithim on the 5k is src-dst mac, and if you add the LAG load balancing which is src-dst ip the 5k switch will work on both algo's at the same time.
i dont know if the 7k behaves the same way.
the workaround for that....is get a 5500 WLC...it has no hardware limitation regarding that.