Login fields in OpenEdge external table

I am setting a portal page and I want to add a login form for the supplier. The login fields (loginName,Password,isActive, LastLogin) are mapped to fields in OpenEdge Supplier table. The registration is ok but when trying to login with a supplier I get this error:

RB_116: Error preparing statement for querySELECT OBJ_ID, PASSWORD FROM RB_OBJ_DATA WHERE OBJ_DEF_ID=? AND LOGINNAME=?[DataDirect][OpenEdge JDBC Driver][OpenEdge] Column "PASSWORD" cannot be found or is not specified for query. (13865)

It seems Rollbase tries to identify the loginName and Password from its own table RB_OBJ_DATA. Is there something that should be set in the sql queries of the object?