Using GeoServer 2.8 and the Data importer plugin I can import shapefiles generated in ArcMap with WGS84 geographic coordinates (EPSG:4326) and UTM+WGS84 projection (epsg:32724). As a reminder, ArcMAP will not add the epsg code to the prj file. That is, it appears that GeoServer can identify the EPSG just based on ESRIs WKT projection file. However, if I try UTM+SIRGAS2000 (epsg:31984) the importer does not recognize the SRS and I have to manually select it. Now, if I substitute the prj file with a more complete one (which includes the EPSG code), geoserver will use it. Is there a way to make GeoServer accept the prj generated by ArcMAP and correctly identify the SIRGAS2000 projection?