RESTEasy throws NoClassDefFoundError: org/codehaus/jackson/map/JsonMappingException$Reference

When I invoke my RESTful Web Service to retrieve JSON data I'm getting a stacktrace about NoClassDefFoundError (see below). This is my META-INF/MANIFESTMF in the .war file:
Manifest-Version: 1.0
Dependencies: org.jboss.resteasy.resteasy-jackson-provider,org.infinis
pan,org.infinispan.client.hotrod,org.jboss.as.controller-client,org.j
boss.dmr,com.google.guava,org.joda.time
Build-Jdk: 1.7.0_07
Built-By: ...
Created-By: Maven Integration for Eclipse

This is the stacktrace:
...
06:20:44,145 INFO [org.jboss.resteasy.spi.ResteasyDeployment] Deploying javax.ws.rs.core.Application: class de.shop.util.JaxRsActivator$Proxy$_$$_WeldClientProxy
06:20:44,571 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/shop].[de.shop.util.JaxRsActivator]] Servlet.service() for servlet de.shop.util.JaxRsActivator threw exception: javax.enterprise.event.ObserverException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) [rt.jar:1.7.0_07]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) [rt.jar:1.7.0_07]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) [rt.jar:1.7.0_07]
at java.lang.reflect.Constructor.newInstance(Constructor.java:525) [rt.jar:1.7.0_07]
at java.lang.Class.newInstance0(Class.java:372) [rt.jar:1.7.0_07]
at java.lang.Class.newInstance(Class.java:325) [rt.jar:1.7.0_07]
at org.jboss.weld.util.reflection.SecureReflections$16.work(SecureReflections.java:344) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.util.reflection.SecureReflectionAccess.run(SecureReflectionAccess.java:52) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.util.reflection.SecureReflectionAccess.runAsInstantiation(SecureReflectionAccess.java:173) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.util.reflection.SecureReflections.newInstance(SecureReflections.java:341) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.injection.Exceptions.rethrowException(Exceptions.java:33) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.injection.Exceptions.rethrowException(Exceptions.java:73) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.injection.MethodInjectionPoint.invokeOnInstanceWithSpecialValue(MethodInjectionPoint.java:162) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.event.ObserverMethodImpl.sendEvent(ObserverMethodImpl.java:245) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.event.ObserverMethodImpl.sendEvent(ObserverMethodImpl.java:233) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.event.ObserverMethodImpl.notify(ObserverMethodImpl.java:213) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.manager.BeanManagerImpl.notifyObservers(BeanManagerImpl.java:590) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.manager.BeanManagerImpl.fireEvent(BeanManagerImpl.java:580) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.weld.manager.BeanManagerImpl.fireEvent(BeanManagerImpl.java:575) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.jboss.solder.servlet.exception.CatchExceptionFilter.doFilter(CatchExceptionFilter.java:74) [solder-impl-3.1.1.Final.jar:3.1.1.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.16.Final.jar:]
at org.jboss.solder.servlet.event.ServletEventBridgeFilter.doFilter(ServletEventBridgeFilter.java:74) [solder-impl-3.1.1.Final.jar:3.1.1.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.16.Final.jar:]
at com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:145) [prettyfaces-jsf2-3.3.3.jar:]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:397) [jbossweb-7.0.16.Final.jar:]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.2.Final.jar:7.1.2.Final]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.2.Final.jar:7.1.2.Final]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.16.Final.jar:]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.16.Final.jar:]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:679) [jbossweb-7.0.16.Final.jar:]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:931) [jbossweb-7.0.16.Final.jar:]
at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_07]
Caused by: javax.servlet.ServletException: Servlet execution threw an exception
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:346) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.16.Final.jar:]
at org.jboss.weld.servlet.ConversationPropagationFilter.doFilter(ConversationPropagationFilter.java:62) [weld-core-1.1.8.Final.jar:2012-04-29 10:45]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.16.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.16.Final.jar:]
at org.jboss.solder.servlet.exception.CatchExceptionFilter.doFilter(CatchExceptionFilter.java:65) [solder-impl-3.1.1.Final.jar:3.1.1.Final]
... 21 more
Caused by: java.lang.NoClassDefFoundError: org/codehaus/jackson/map/JsonMappingException$Reference
at org.codehaus.jackson.map.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:166) [jackson-mapper-asl-1.9.2.jar:1.9.2]
at org.codehaus.jackson.map.ser.BeanSerializer.serialize(BeanSerializer.java:112) [jackson-mapper-asl-1.9.2.jar:1.9.2]
...