To be honest, in the end ALL phone cameras are physically crap. The difference makes the software. Good cameras have a large sensor, Fullstop! (and a optic with more than one element)
Anyway I also own a N900. And the camera is definetely and without ANY doubt worse than the camera of the Pro1 (Even withe the Sailfish camera app). And I don't know any possibility to tune the camera of the N900. So it doesn't matter if the N900 is heavily modded, which mine is as well.