I am creating a report using iReport Designer for OpenERP, with sql method and parameters ( $P{start_date} and $P{end_date} ). Report contains main report and sub reports (2), and sql methods applied in the sub reports. Main report was given 2 parameters : 1. $P{start_date}, Parameter Class --> java.util.Date, Use as a prompt : TRUE 2. $P{end_date}, Parameter Class --> java.util.Date, Use as a prompt : TRUE Sub Reports was given 2 parameters : 1. $P{start_date}, Parameter Class --> java.util.Date, Use as a prompt : TRUE 2. $P{end_date}, Parameter Class --> java.util.Date, Use as a prompt : TRUE sub reports execute the following SQL syntax: SELECT a.name AS kode_jb, a.deskripsi AS jns_blnja, b.tgl_transaksi, b.output FROM jenis_belanja a JOIN transaksi_bos b ON a.id=b.jns_belanja WHERE b.tgl_transaksi BETWEEN $P{start_date} AND $P{end_date}after I apply reports to OpenERP, result is that there is an error warning: " Failed to invoke method execute in class com.nantic.jasperreports.JasperServer: Error evaluating expression : Source text : $P{end_date} "I do have an alternative way to add a third parameter ( $P{date_token}, Parameter Class --> java.util.String, Use as a prompt : FALSE and default value expression --> ($P{start_date} == null || $P{end_date} == null ? "AND 0=0" :"AND b.tgl_transaksi BETWEEN '" + new SimpleDateFormat("yyyy-MM-dd").format($P{start_date}) + "' AND '" + new SimpleDateFormat("yyyy-MM-dd").format($P{end_date}) +"'" ). )but the same error warning appears: Failed to invoke method execute in class com.nantic.jasperreports.JasperServer: Error evaluating expression : Source text : $P{end_date}.anyone can help me find a solution ? ThanksBaim nb : sorry, my english is not perfect.