The attached image shows two text rendering problems.
The one lower in the image is that the text is not above the dashed line as in the other ways (set via text-dy in Cascadenik). I noticed a few other such cases, but more than 99% of the ways are fine.
The problem in the upper part occurs exactly at a tile boundary, the text is supposed to read "Grüner Strich/Roter Punkt".
You can look at the tiles live at http://opentiles.com/cmarqu/?zoom=15&lat=50.96286&lon=14.06721&layers=00B000000 (Layer "Hike & Bike 2009-01-19", in case the layer order changes).
[springmeyer] kick to next milestone
The URL doesn't work anymore, here is a new one. See "Schwarzweg" in http://hikebikemap.de/?zoom=15&lat=50.94988&lon=14.17918&layers=B0000FFFFF or http://toolserver.org/tiles/hikebike/15/17674/10977.png
There are also examples where the text is completely at the opposite side of the way, like "Ochelweg" here: http://hikebikemap.de/?zoom=15&lat=50.9434&lon=14.14912&layers=B0000FFFFF and http://toolserver.org/tiles/hikebike/15/17671/10978.png
(This is with a pre-2 Mapnik.)
Text positions unpredictably jumping is solved in mapnik 2. However it depends on the direction of your way whether it is above or below the way.