How to disable alt+click from moving windows in Unity 2D?

How can I disable the alt+click combination from moving windows in Ubuntu 11.10 (unity-2d)?

With Unity-2D, this is controlled using the /apps/metacity/general/mouse_button_modifier GConf key. To disable Alt+Click dragging, run

gconftool-2 --set /apps/metacity/general/mouse_button_modifier --type string disabled

To re-enable it, run

gconftool-2 --set /apps/metacity/general/mouse_button_modifier --type string '<Alt>'

Note that this GConf key controls several mouse shortcuts:

• Alt+Click: Move windows
• Alt+Middle Click: Resize windows
• Alt+Right Click: Open a generic window menu

N.B: Disabling the modifier in this way can lead to the Alt+Drag behavior when no modifier keys are pressed (Every drag behaves like Alt+drag) Setting the modifier to '<SUPER>' makes the Super/Windows key the modifier. Alt+Drag can then be used by applications, and Super+Drag to move the window.

gconftool-2 --set /apps/metacity/general/mouse_button_modifier --type string '<SUPER>'

for Unity 3D

• How to disable window move with alt + left mouse button?