Hi Spexx,
If you have a look at reply#13 of this thread, you should find a link which describes just the application you were referring to. This uses a cheap as chips, BSH203 PFET and a BC547 transistor, plus a couple of resistors. Draws probably nanoampere levels when switched off, as opposed to the 11 microamperes when the divider is switched on. May be it will be of some help to you?
Felix, maybe it's just me but I tried that JeeLab's 10Mohm, 4M7ohm, 0.1 uF cap trick and when I tried checking the divider voltage as a 10 digit integer value, I found too big an error for my comfort zone. Pity because I would really have liked to get that divider current down low. That's why I ended up using a 110kohm, 220kohm divider for my little Moteino Shield v1.1. Whether the 0.1uF cap was installed made no difference. As I said, maybe it's just me!
cheers,