[SailfishDevel] change resolution of the emulator?

[Wim de Vries]

Hi,
I want to change the screen resolution to at least the lowest HD 
(720x1280), since the Jolla phone would be HD...
I am not very virtualbox knowledgeable, but what I can digest from 
googling a lot, is that the target OS has to set the resolution. So, 
that would be in Sailfish itself.
Any ideas how to do that? Or is this not yet feasible in the alpha?
Thanks.