The only viable solution I found until now is to use GPE (http://gpe.linuxtogo.org/). It's still a bit buggy, but for my usage pattern it may be sufficient (time will tell). I also sync the GPE calendar with Google Calendar, in order to easily obtain ICS files to synchronize with other applications / people...

But it's true that the PIM scene on the N8x0 is still a bit lacking of good products

And I agree that relying on GarnetVM for doing PIM work is not really an ecstatic experience....