Soap UI-4.0.0- Exception in thread "XpcMessageLoop" java.lang.ExceptionInInitializerError

When I tried to run soapui.sh from inside the [soapui_home]/bin on my Ubuntu 13.04 I got the given below error.

Exception in thread "XpcMessageLoop" java.lang.ExceptionInInitializerError
    at com.teamdev.xpcom.a.b.a.a.(Unknown Source)
    at com.teamdev.xpcom.XpcMessageLoop.(Unknown Source)
    at com.teamdev.xpcom.XpcMessageLoop.getInstance(Unknown Source)
    at com.teamdev.xpcom.b$a.run(Unknown Source)
Caused by: java.lang.RuntimeException: java.io.FileNotFoundException: Library libgtk-x11-2.0 not found at any known locations !
    at com.jniwrapper.linux.utils.LinuxLibraryLoader.(LinuxLibraryLoader.java:90)
    at com.jniwrapper.gtk.GtkLib.(GtkLib.java:25)
    at com.jniwrapper.gtk.GtkLib.getFunction(GtkLib.java:41)
    at com.jniwrapper.gtk.GTK.(GTK.java:45)
    ... 4 more
Caused by: java.io.FileNotFoundException: Library libgtk-x11-2.0 not found at any known locations !
    ... 8 more

The reason for this issue is Soap UI 4.0.0 is known to this version and to overcome it you have to uncomment the following line from the soapui.sh.

JAVA_OPTS="$JAVA_OPTS -Dsoapui.jxbrowser.disable=true"

And restart Soap UI.