Anyone trying to connect Geoserver to an ArcSDE dataset stored as (ESRI) EPSG: 54001 will quickly find that not all Plate Carree's are created equal. Geoserver does not like ESRI's choice of ellipsoid, which means tweaking the parameters slightly. Follow these simple steps to make EPSG:54001 operational in Geoserver.
1. Edit ../webapps/geoserver/data/user_projections/epsg.properties in your Tomcat context.
2. Add a new line at the end of the file and append the following text as 1 line. Syntax is critical.
54001= PROJCS["WGS 84 / Plate Carree", GEOGCS["WGS 84", DATUM["World Geodetic System 1984", SPHEROID["WGS 84", 6378137.0, 298.257223563, AUTHORITY["EPSG","7030"]], AUTHORITY["EPSG","6326"]], PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]], UNIT["degree", 0.017453292519943295], AXIS["Geodetic longitude", EAST], AXIS["Geodetic latitude", NORTH], AUTHORITY["EPSG","4326"]], PROJECTION["Equidistant Cylindrical (Spherical)", AUTHORITY["EPSG","9823"]], PARAMETER["central_meridian", 0.0], PARAMETER["latitude_of_origin", 0.0], PARAMETER["standard_parallel_1", 0.0],PARAMETER["false_easting", 0.0],PARAMETER["false_northing", 0.0],UNIT["m", 1.0],AXIS["Easting",EAST],AXIS["Northing", NORTH],AUTHORITY["EPSG","54001"]]
3. Restart Geoserver.
4. In your Geoserver Admin page select "Demos" and click on the "SRS List" link.
5. Search for either "54001" or "Plate Carree" and view the results.
Your projection should be in this list. Remember to keep an eye out on the Geoserver log for errors.
