By trying to upgrade AS from 7.0.2 to 7.1.2 I got into an issue where some parts of the JDK where not being available to my deployed artifact. The execution of some actions failed with the ClassNotFoundException importing the com.sun.image.codec.jpeg.ImageFormatException which is present it JDK's rt.jar. The only solution was to add com/sun/image/codec to the paths in the sun's jdk jboss module.