After a ARMv6HF cross build, if I copy the results over an 8u6 JDK, I get runtime errors which I do not get if I use -Djava.ext.dirs=path-to-lib-ext-in-same-build

pi@raspberrypi ~/shared/jars $ sudo /opt/jdk/bin/java -cp Hello.jar hello.HelloSanity
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: java.lang.UnsatisfiedLinkError: com.sun.glass.ui.monocle.linux.Udev._open()J
at com.sun.javafx.tk.quantum.QuantumToolkit.startup(QuantumToolkit.java:296)
at com.sun.javafx.application.PlatformImpl.startup(PlatformImpl.java:216)
at com.sun.javafx.application.LauncherImpl.startToolkit(LauncherImpl.java:653)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:314)
at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:305)
... 5 more
Caused by: java.lang.UnsatisfiedLinkError: com.sun.glass.ui.monocle.linux.Udev._open()J
at com.sun.glass.ui.monocle.linux.Udev._open(Native Method)
at com.sun.glass.ui.monocle.linux.Udev.<init>(Udev.java:68)
at com.sun.glass.ui.monocle.linux.Udev.getInstance(Udev.java:54)
at com.sun.glass.ui.monocle.linux.LinuxInputDeviceRegistry.<init>(LinuxInputDeviceRegistry.java:77)
at com.sun.glass.ui.monocle.linux.LinuxPlatform.createInputDeviceRegistry(LinuxPlatform.java:19)
at com.sun.glass.ui.monocle.NativePlatform.getInputDeviceRegistry(NativePlatform.java:58)
at com.sun.glass.ui.monocle.MonocleApplication.<init>(MonocleApplication.java:78)
at com.sun.glass.ui.monocle.MonoclePlatformFactory.createApplication(MonoclePlatformFactory.java:45)
at com.sun.glass.ui.Application.run(Application.java:145)
at com.sun.javafx.tk.quantum.QuantumToolkit.startup(QuantumToolkit.java:281)
... 9 more