During launching the JNLP the following NPE is thrown.

{{java.lang.NullPointerException
at org.hudson.trayapp.gui.tray.TrayIconImplementation.displayException(TrayIconImplementation.java:36)
at org.hudson.trayapp.model.Server.isHudsonBuild173orGreater(Server.java:294)
at org.hudson.trayapp.model.Server.update(Server.java:70)
at org.hudson.trayapp.model.Server.<init>(Server.java:45)
at org.hudson.trayapp.model.Model.addServer(Model.java:65)
at org.hudson.trayapp.HudsonTrayApp.<init>(HudsonTrayApp.java:75)
at org.hudson.trayapp.HudsonTrayApp.getHudsonTrayAppInstance(HudsonTrayApp.java:47)
at org.hudson.trayapp.HudsonTrayApp.main(HudsonTrayApp.java:39)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.sun.javaws.Launcher.executeApplication(Unknown Source)
at com.sun.javaws.Launcher.executeMainClass(Unknown Source)
at com.sun.javaws.Launcher.doLaunchApp(Unknown Source)
at com.sun.javaws.Launcher.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)}}

{{<jnlp codebase="http://valid-ip:8080/jenkins/plugin/hudsontrayapp/">
<information>
<title>Hudson Tray Application</title>
<vendor>David Hayes</vendor>
<offline-allowed/>
</information>
<security>
<all-permissions/>
</security>
<resources>
<jar href="HudsonTrayApp.jar" main="true" download="eager"/>
<j2se version="1.6+" initial-heap-size="32m" max-heap-size="32m"/>
<j2se version="1.5" initial-heap-size="32m" max-heap-size="32m">
<resources>
<extension name="jdic" href="jdic"/>
</resources>
</j2se>
<j2se version="1.4" initial-heap-size="32m" max-heap-size="32m">
<resources>
<extension name="jdic" href="jdic"/>
</resources>
</j2se>
</resources>
<application-desc main-class="org.hudson.trayapp.HudsonTrayApp">
<argument>server=http://valid-ip:8080/jenkins/</argument>
</application-desc>
</jnlp>}}