Java Agents in Notes

I use java agents in Domino to create reports to PDF. These all work fine under Notes 6 but when running the report in the 8.5 client I get the error below. The error only seems to occur for those reports in which I use Swing progress bars. Can anyone assist? Why are security errors stopping the report when they didn’t before?

java.security.AccessControlException: Access denied (java.lang.RuntimePermission exitVM.0)

at java.security.AccessControlException.<init>(Unknown Source)

at java.security.AccessController.checkPermission(AccessController.java:108)

at java.lang.SecurityManager.checkPermission(SecurityManager.java:545)

at COM.ibm.JEmpower.applet.AppletSecurity.superDotCheckPermission(AppletSecurity.java:1440)

at COM.ibm.JEmpower.applet.AppletSecurity.checkRuntimePermission(AppletSecurity.java:1302)

at COM.ibm.JEmpower.applet.AppletSecurity.checkPermission(AppletSecurity.java:1516)

at COM.ibm.JEmpower.applet.AppletSecurity.checkPermission(AppletSecurity.java:1455)

at java.lang.SecurityManager.checkExit(SecurityManager.java:757)

at javax.swing.JFrame.setDefaultCloseOperation(JFrame.java:390)

at ReportsEnginePDF.createProgressBar(ReportsEnginePDF.java:144)

at Improvements_Timeliness_Report.run(Improvements_Timeliness_Report.java:48)

at JavaAgent.NotesMain(JavaAgent.java:32)

at lotus.domino.AgentBase.runNotes(Unknown Source)

at lotus.domino.NotesThread.run(Unknown Source)