I found this article http://community.jaspersoft.com/wiki/multiple-datasources-ireport-lists-tables-and-subreports that details how to use a seperate data source for a list or table element. This works great in iReport, however, when I load the report into the server repository and run the report in iReport, I recieve the following error:
java.lang.Exception: 1 - Error evaluating expression :
Source text : $P{connection}
at com.jaspersoft.ireport.jasperserver.ws.WSClient.runReport(WSClient.java:403)
at com.jaspersoft.ireport.jasperserver.ws.WSClient.runReport(WSClient.java:320)
at com.jaspersoft.ireport.jasperserver.ReportRunner.run(ReportRunner.java:70)
at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:572)
at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997)
$P{connection} is the parameter I am using to insert the new connection. When I placed the report in the repository, I set up an input control with a single select list of values, with the value being the connection string.