Steps to reproduce -
1. Create a maze area like shown in the screenshots.
2. Dispense a zombie or creeper egg on the far side of the wall to create a zombie.

Observed result -

The mob may jump on the first glass plane (obviously knows there's a player), but then stops, or spins, or some other crazy AI movement. The AI will reset if the player moves sideways and the line of sight is re-established.

Expected result - The AI should know that it can move through the glass panes (especially now that the glass pane model has changed).