The latest release (1.0.5) is meant for users working with JCO 2.0.
SAP2Java 1.0.4 now has a new improved plugin - GUI for Eclipse. It also includes a partial API Documentation and utility classes/prototypes for SAP BAPIs BAPI_COMPANYCODE_GETLIST, BAPI_COMPANYCODE_GETDETAILS and BAPI_CUSTOMER_GETLIST.
It also provides instructions on how to use the application without the plugin gui (for non eclipse users) !
See http://eclipsesap2java.sourceforge.net .