Item frames cause lag / huge FPS drops when rendered

Playing on a singleplayer map I made a room with almost every space of the walls having an item frame on it.
Whenever I turn to the direction of the item frame room my FPS lags itself to death.
Very debilitating as I essentially can't look in that direction and work - my FPS isn't very good as it is.

Here is an example of the lag in 1.6.4 using a 1.2.5 launcher
http://www.youtube.com/watch?v=ktBUQwDY0G8

Here is an example of the lag in 1.8.1-pre4 using a 1.5.3 launcher
https://www.youtube.com/watch?v=CueUB8Z2DAw&

Seems to be worse with animated items in frames.