PS4: Only one controller button can be unassigned

I'm really pleased with the PS4 beta; it's a vast improvement over the PS3 version. But I noticed a problem with controller configuration. On the PS3 version, I disabled both the L3 and R3 buttons, since I tend to accidentally panic-press them in certain situations (typically involving fighting Titan), but apparently the PS4 version doesn't support turning off more than one button.

Time: Irrelevant
Frequency: Always
World name: Irrelevant
Character name: Irrelevant
NPC name: Irrelevant
Monster name: Irrelevant
Class/Level: Irrelevant
Party or solo: Irrelevant
In-game time: Irrelevant
Area and coordinates: Irrelevant
Steps:
1. Log into the game, choose a character
2. Press Options to get to the main menu
3. Choose System -> System Configuration
4. Choose Controller Settings
5. Press the "Begin" button
6. Choose any pop-up (I chose the L3 button) and assign it to "Not Assigned"
7. Choose any other pop-up (I chose R3) and assign it to "Not Assigned"

Expected results:
Both buttons are expected to be disabled.

Actual results:
Only the last button you disabled is actually disabled.

Regression:
This worked correctly in the PS3 version.

Model Number of the PlayStation®4 You Are Using
- Model Number: There's only one right now in North America

Information About the Peripherals You Are Using
-Type: PS4 controller
-Maker:
-Model Number: