[Tilesathome] Lowzoom projektion error in poland

[Damian Sulewski]

Hi,
go to:
http://informationfreeway.org/?lat=54.071926328741654&lon=18.457308032419494&zoom=11&layers=B000F000F

and switch between Mapnik and t at h.

You will see the town Skarszewy jumping up and down. 
This is only for zoom level 11 to 1, what can cause this?

Greetings,

Damian