You are right. RMI will not work for anything which is not serializable. Conside the following options:

1. Write a bean/value object class (which implements seralizable) that can store all the data available with one record. Iterate thru the resultset, populate the value object, put the value object in collection. When done return the collection back to the client

2. Specifically for resultsets - use JDBC Rowset API (http://developer.java.sun.com/developer/earlyAccess/crs) with which you can convert your resultset into a CachedRowset (which is serializable) and return it to client.