Unsupported execution environment [JavaSE-1.7] we have [OSGi/Minimum-1.1, J2SE-1.1, OSGi/Minimum-1.2, J2SE-1.2, J2SE-1.3, J2SE-1.4, J2SE-1.5, JavaSE-1.6]
I believe You have built your classes with 1.7 java when you actually have 1.6 at max in jboss.
Does your jboss run on 1.6 java while builds are made on 1.7?