play class loader issue.

gistfile1.txt

play.server.ServletWrapper: java.lang.UnsupportedClassVersionError: DocViewerPlugin : Unsupported major.minor version 51.0
       at java.lang.ClassLoader.defineClass1(Native Method) [:1.6.0_27]
       at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)[:1.6.0_27]
       at java.lang.ClassLoader.defineClass(ClassLoader.java:615) [:1.6.0_27]
       at play.classloading.ApplicationClassloader.loadApplicationClass(ApplicationClassloader.java:118) [play-1.2.4.jar:]
       at play.classloading.ApplicationClassloader.getAllClasses(ApplicationClassloader.java:401) [play-1.2.4.jar:]
       at play.Play.preCompile(Play.java:570) [play-1.2.4.jar:]
       at play.Play.init(Play.java:299) [play-1.2.4.jar:]
       at play.server.ServletWrapper.contextInitialized(ServletWrapper.java:77) [play-1.2.4.jar:]
       at org.apache.catalina.core.StandardContext.contextListenerStart(StandardContext.java:3368) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
       at org.apache.catalina.core.StandardContext.start(StandardContext.java: 3821) [jbossweb-7.0.1.Final.jar:7.0.2.Final]
       at org.jboss.as.web.deployment.WebDeploymentService.start(WebDeploymentService.java:70) [jboss-as-web-7.0.2.Final.jar:7.0.2.Final]
       at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1824)
       at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1759)
       at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [:1.6.0_27]
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [:1.6.0_27]
       at java.lang.Thread.run(Thread.java:662) [:1.6.0_27]