Here I post my old project when I used to manage iSeries system. I made application named iSeries Data Extractor Free. It might be useful for you.
iSeries Data Extractor Free is a tool for exporting/extracting database from iSeries to RDBMS. For now, the supported RDBMS are Microsoft SQL Server, Oracle, MySql, and PostgreSQL.
It is free software, but it has some limitation like it will proceed up to 100,000 records and only zoned decimal, packed decimal, string data types that can be processed.
It is developed using Java. So, it is possible to run under any kind of operating system. The extraction process itself uses Java Database Connectivity (JDBC).
Note : I try to develop a version equipped with more features and faster process, but unfortunately I cannot access iSeries system anymore.