Log4j is required in order to process the deployment. Log4j dependency must be included on the classpath in order to example to work.

Can be solved by following activation:

<jboss-deployment-structure xmlns="urn:jboss:deployment-structure:1.0">
    <deployment>
        <dependencies>
            <module name="org.apache.log4j" slot="main" export="true" />
        </dependencies>
    </deployment>
</jboss-deployment-structure>

Or by changing scope for log4j artifact.

Error log for reference:

15:38:10,823 INFO  [org.springframework.beans.factory.support.DefaultListableBeanFactory] (MSC service thread 1-4) Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@e74e382: defining beans [org.springframework.beans.factory.config.PropertyPlaceholderConfigurer#0,org.springframework.jdbc.datasource.init.DataSourceInitializer#0,dataSource,org.springframework.context.weaving.AspectJWeavingEnabler#0,org.springframework.context.config.internalBeanConfigurerAspect,loadTimeWeaver,org.springframework.beans.factory.config.PropertyPlaceholderConfigurer#1,entityManagerFactory,transactionManager,org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.annotation.internalPersistenceAnnotationProcessor,org.springframework.aop.config.internalAutoProxyCreator,org.springframework.transaction.annotation.AnnotationTransactionAttributeSource#0,org.springframework.transaction.interceptor.TransactionInterceptor#0,org.springframework.transaction.config.internalTransactionAdvisor,org.springframework.samples.petclinic.aspects.UsageLogAspect#0,clinic]; root of factory hierarchy
15:38:10,827 SEVERE [org.springframework.web.context.ContextLoader] (MSC service thread 1-4) Context initialization failed: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.samples.petclinic.aspects.UsageLogAspect#0' defined in ServletContext resource [/WEB-INF/spring/applicationContextJpa.xml]: Error setting property values; nested exception is org.springframework.beans.PropertyBatchUpdateException; nested PropertyAccessExceptions (1) are:
PropertyAccessException 1: org.springframework.beans.MethodInvocationException: Property 'historySize' threw exception; nested exception is java.lang.NoClassDefFoundError: org/apache/log4j/Level
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1361) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1086) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:293) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:290) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:192) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895) [spring-context-3.0.6.RELEASE.jar:]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425) [spring-context-3.0.6.RELEASE.jar:]
        at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:282) [spring-web-3.0.6.RELEASE.jar:]
        at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:204) [spring-web-3.0.6.RELEASE.jar:]
        at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47) [spring-web-3.0.6.RELEASE.jar:]
        at org.apache.catalina.core.StandardContext.contextListenerStart(StandardContext.java:3392) [jbossweb-7.0.3.Final-redhat-1.jar:]
        at org.apache.catalina.core.StandardContext.start(StandardContext.java:3850) [jbossweb-7.0.3.Final-redhat-1.jar:]
        at org.jboss.as.web.deployment.WebDeploymentService.start(WebDeploymentService.java:77) [jboss-as-web-7.1.0.Beta1-redhat-1.jar:]
        at org.jboss.msc.service.ServiceControllerImpl$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]
Caused by: org.springframework.beans.PropertyBatchUpdateException; nested PropertyAccessExceptions (1) are:
PropertyAccessException 1: org.springframework.beans.MethodInvocationException: Property 'historySize' threw exception; nested exception is java.lang.NoClassDefFoundError: org/apache/log4j/Level
        at org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:102) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:58) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1358) [spring-beans-3.0.6.RELEASE.jar:]
        ... 21 more

15:38:10,832 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/petclinic]] (MSC service thread 1-4) Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.samples.petclinic.aspects.UsageLogAspect#0' defined in ServletContext resource [/WEB-INF/spring/applicationContextJpa.xml]: Error setting property values; nested exception is org.springframework.beans.PropertyBatchUpdateException; nested PropertyAccessExceptions (1) are:
PropertyAccessException 1: org.springframework.beans.MethodInvocationException: Property 'historySize' threw exception; nested exception is java.lang.NoClassDefFoundError: org/apache/log4j/Level
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1361) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1086) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:293) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:290) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:192) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895) [spring-context-3.0.6.RELEASE.jar:]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425) [spring-context-3.0.6.RELEASE.jar:]
        at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:282) [spring-web-3.0.6.RELEASE.jar:]
        at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:204) [spring-web-3.0.6.RELEASE.jar:]
        at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47) [spring-web-3.0.6.RELEASE.jar:]
        at org.apache.catalina.core.StandardContext.contextListenerStart(StandardContext.java:3392) [jbossweb-7.0.3.Final-redhat-1.jar:]
        at org.apache.catalina.core.StandardContext.start(StandardContext.java:3850) [jbossweb-7.0.3.Final-redhat-1.jar:]
        at org.jboss.as.web.deployment.WebDeploymentService.start(WebDeploymentService.java:77) [jboss-as-web-7.1.0.Beta1-redhat-1.jar:]
        at org.jboss.msc.service.ServiceControllerImpl$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]
Caused by: org.springframework.beans.PropertyBatchUpdateException; nested PropertyAccessExceptions (1) are:
PropertyAccessException 1: org.springframework.beans.MethodInvocationException: Property 'historySize' threw exception; nested exception is java.lang.NoClassDefFoundError: org/apache/log4j/Level
        at org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:102) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:58) [spring-beans-3.0.6.RELEASE.jar:]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1358) [spring-beans-3.0.6.RELEASE.jar:]
        ... 21 more

15:38:10,872 ERROR [org.apache.catalina.core.StandardContext] (MSC service thread 1-4) Error listenerStart
15:38:10,873 ERROR [org.apache.catalina.core.StandardContext] (MSC service thread 1-4) Context [/petclinic] startup failed due to previous errors
15:38:10,889 INFO  [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/petclinic]] (MSC service thread 1-4) Closing Spring root WebApplicationContext
15:38:10,891 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-4) MSC000001: Failed to start service jboss.web.deployment.default-host./petclinic: org.jboss.msc.service.StartException in service jboss.web.deployment.default-host./petclinic: failed to start context
        at org.jboss.as.web.deployment.WebDeploymentService.start(WebDeploymentService.java:82)
        at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1824) [jboss-msc-1.0.1.GA-redhat-1.jar:]
        at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1759) [jboss-msc-1.0.1.GA-redhat-1.jar:]
        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]