We have downloaded OSM data for our region and loaded them into PostGIS using osm2pgsql. So far so good. On top we have GeoServer and we would like to expose the OSM data using WMS. We would as well like to style data like in "standard" OpenStreetMaps (e.g. osm.org) as this cartography is well designed. We have tried to download som standard SLD for OSM data, but there seem to all sorts of problems using these SLDs (XML parsing errors, invalid content, etc.).
Any good ideas how to reuse an OSM SLD to style OSM through WMS?