Downloaded the version for Linux, and tried to start it but got an error.
ian@ian-desktop:~/Downloads/IBJts$ java -cp jts.jar:pluginsupport.jar:jcommon-1.0.0.jar:jfreechart-1.0.0.jar:jhall.jar:other.jar:riskfeed.jar:rss.jar -Xmx256M jclient.LoginFrame .
java.lang.NoSuchMethodException: getLAFState
at java.lang.Class.getDeclaredMethod(libgcj.so.81)
at feature.search.recorder.JtsMultiLookAndFeel.a(JtsMultiLookAndFeel.java:99)
at jclient.LoginFrame.main(LoginFrame.java:620)
Exception in thread "JTS-Main" java.lang.AssertionError
at jutils.qe.G(qe.java:780)
at jutils.qe.(qe.java:137)
at jutils.qe.(qe.java:120)
at java.lang.Class.initializeClass(libgcj.so.81)
at jutils.wd.k(wd.java:857)
at jclient.LoginFrame.main(LoginFrame.java:664)

Do I have the wrong version of java or something? I've updated to the latest version using Synaptic. Do I need to do something else?

All advice gratefully received.