EXpanding volume of a particles system during animation ?

Hi,

Suppose we have cube at start that emits particles from volume, i.e. 10 particles.
Is it possible to expand the volume of the emitter volume (cube) during an animation?
At end, the cube is now 2 times the original one.
The animation needed is a kind of diffusion of a known number of particles within a volume.

Thanks.

Just tried a scaling of the emiter during animation.
it worked.