Ubuntu and bumblebee and intel problem

I have a brain teaser that i can't solve. When 12.04 (64bits) came out, i did a fresh install and then installed bumblebee with:

sudo add-apt-repository ppa:bumblebee/stable
sudo apt-get install bumblebee bumblebee-nvidia

And Ubuntu recognized (System Settings - Details) Intel Card for primary card, and i could launch applications with optirun.

I have:

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: NVIDIA Corporation GF119 [GeForce GT 520MX] (rev ff)

Now, a few days back, i did the exact same thing, installed from the same DVD everything the same, installed bumblebee the same way.

Nvidia with Optirun works fine, but Ubuntu doesn't have 3D effects:

root@deathstar:~# optirun /usr/lib/nux/unity_support_test -p
OpenGL vendor string:   NVIDIA Corporation
OpenGL renderer string: GeForce GT 520MX/PCIe/SSE2
OpenGL version string:  4.2.0 NVIDIA 295.40

Not software rendered:    yes
Not blacklisted:          yes
GLX fbconfig:             yes
GLX texture from pixmap:  no
GL npot or rect textures: yes
GL vertex program:        yes
GL fragment program:      yes
GL vertex buffer object:  yes
GL framebuffer object:    yes
GL version is 1.4+:       yes

Unity 3D supported:       no

I never did anything to install Intel drivers (except installing mesa-utils), before bumblebee got everything working, but now i can't get Ubuntu to get Unity with 3D.

Can someone help me please get Unity 3d working?

Your help will be much appreciated