Hi TIm, thanks for the answer. Hope you will be able to solve it once. I tatally agree with you, maps for wikipedia don't require a fast update, and for the time I'll use the ITO layer, which seems to be up to date, at least reflect the edits I made in the last weeks/month.
What was strange, is that when I did some "lightening" edits in one region, and wanted to check the results a few days later, I normally got at first the "...more OSM coming soon" logo on the tiles. Zoom OUT then zoom IN, and normally the logo disappear (if the server is not overloaded) but then the layer doesn't reflect the las t edits. That's why I thought that the rendering was made correctly (recently) but on an old database version. And once you've got a region rendered wrongly, I never see the "...more OSM coming soon" logo coming, event If I look again on the same region several month later. If this can help you find the problem / solution I am glad.
Ok for the "dirty trick". on Mapnik.
Best Regards
Yves
PS: BTW I didn't receive the map-l mails (nor mine, nor yours), I had to look in the archive to find your answer. Maybe my subscription was too "new", or the fact that I've asked for a grouped delivery of mails make it takes several days to be delivered?