This work fine using the jasper studio.
After a couple of our searching on google I came out that jasperreport is using a olg version of Rhino V1.7R3 the current version of Rhino is V1.7.6. The issue is in the ScriptRuntime class where there the method add(Object String has been remove since V1.7R3) so i is not possible to concat using the + sign the workarround is to use the concat function. Is it planed to upgrade jasperreport to rhino 1.7.6 ? Is there another way to work arround without in order to be able to use the + sign