Some years ago I was asked to design a report in MS Excel format in OEBS. Also received xls file had to be zipped and sent by email. Last two requirements could be easy implemented using Java. Since I had already decided to use Java I attempted to integrate JasperReports into OEBS too. In my oppinion JasperReports is more powerful reports' generator than Oracle Reports 6. Withal JasperReports has build-in export a report in xls format.
In those days I used OEBS 188.8.131.52. It had jdk 1.4.2_04 on board. There were some troubles with choice of JasperReports version. Although JasperSoft declared that last version compatible with jdk 1.4 was 3.7.1, in my case only 3.2.1 version shew stable work. Unfortunately I can't find respective link on Jasper Forum now to prove this assertion.
Well, let's do, step by step, all things we need to receive a simple report in xls format.