Downloading Ovi Maps without a network connection

Unlike Navicore/Wayfinder on previous Maemo devices, Ovi Maps on the N900 downloads maps on demand. This is obviously a problem if you're going somewhere abroad and don't want to pay extortionate data roaming charges.
Fortunately, S60 Ovi Maps users also have the same problem, and the solution is straightforward:

1. Scroll down the above URL and download the maps for the countries you are interested in. Obviously skip the instructions about downloading Ovi Maps - the N900 has Ovi Maps already installed!
2. Unzip the maps into cities/diskcache on the big VFAT partition (mounted under MyDocs) on your N900.
   
3. That's it!

Some of the files you may already have, I've chosen to overwrite them; YMMV.
However, as far as I can tell, searching for locations still requires a network connection :-(

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