I have a web client and a EJB project, which I created with Eclipse 3.4. When I want to deploy it on Jboss 5.0.1, I receive the error below. I searched a lot but I wasn't able to find a solution to this.

18:21:21,899 INFO  [ServerImpl] Starting JBoss (Microcontainer)...
18:21:21,900 INFO  [ServerImpl] Release ID: JBoss [Morpheus] 5.0.1.GA (build: SVNTag=JBoss_5_0_1_GA date=200902231221)
18:21:21,900 INFO  [ServerImpl] Bootstrap URL: null
18:21:21,900 INFO  [ServerImpl] Home Dir: /Applications/jboss-5.0.1.GA
18:21:21,900 INFO  [ServerImpl] Home URL: file:/Applications/jboss-5.0.1.GA/
18:21:21,901 INFO  [ServerImpl] Library URL: file:/Applications/jboss-5.0.1.GA/lib/
18:21:21,901 INFO  [ServerImpl] Patch URL: null
18:21:21,901 INFO  [ServerImpl] Common Base URL: file:/Applications/jboss-5.0.1.GA/common/
18:21:21,902 INFO  [ServerImpl] Common Library URL: file:/Applications/jboss-5.0.1.GA/common/lib/
18:21:21,902 INFO  [ServerImpl] Server Name: default
18:21:21,902 INFO  [ServerImpl] Server Base Dir: /Applications/jboss-5.0.1.GA/server
18:21:21,902 INFO  [ServerImpl] Server Base URL: file:/Applications/jboss-5.0.1.GA/server/
18:21:21,902 INFO  [ServerImpl] Server Config URL: file:/Applications/jboss-5.0.1.GA/server/default/conf/
18:21:21,902 INFO  [ServerImpl] Server Home Dir: /Applications/jboss-5.0.1.GA/server/default
18:21:21,902 INFO  [ServerImpl] Server Home URL: file:/Applications/jboss-5.0.1.GA/server/default/
18:21:21,903 INFO  [ServerImpl] Server Data Dir: /Applications/jboss-5.0.1.GA/server/default/data
18:21:21,903 INFO  [ServerImpl] Server Library URL: file:/Applications/jboss-5.0.1.GA/server/default/lib/
18:21:21,903 INFO  [ServerImpl] Server Log Dir: /Applications/jboss-5.0.1.GA/server/default/log
18:21:21,903 INFO  [ServerImpl] Server Native Dir: /Applications/jboss-5.0.1.GA/server/default/tmp/native
18:21:21,903 INFO  [ServerImpl] Server Temp Dir: /Applications/jboss-5.0.1.GA/server/default/tmp
18:21:21,903 INFO  [ServerImpl] Server Temp Deploy Dir: /Applications/jboss-5.0.1.GA/server/default/tmp/deploy
18:21:22,669 INFO  [ServerImpl] Starting Microcontainer, bootstrapURL=file:/Applications/jboss-5.0.1.GA/server/default/conf/bootstrap.xml
18:21:23,535 INFO  [VFSCacheFactory] Initializing VFSCache [org.jboss.virtual.plugins.cache.CombinedVFSCache]
18:21:23,541 INFO  [VFSCacheFactory] Using VFSCache [CombinedVFSCache[real-cache: null]]
18:21:23,942 INFO  [CopyMechanism] VFS temp dir: /Applications/jboss-5.0.1.GA/server/default/tmp
18:21:23,943 INFO  [ZipEntryContext] VFS force nested jars copy-mode is enabled.
18:21:26,263 INFO  [ServerInfo] Java version: 1.5.0_16,Apple Inc.
18:21:26,264 INFO  [ServerInfo] Java Runtime: Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_16-b06-284)
18:21:26,264 INFO  [ServerInfo] Java VM: Java HotSpot(TM) Server VM 1.5.0_16-133,Apple Inc.
18:21:26,264 INFO  [ServerInfo] OS-System: Mac OS X 10.5.6,i386
18:21:26,336 INFO  [JMXKernel] Legacy JMX core initialized
18:21:30,432 INFO  [ProfileServiceImpl] Loading profile: default from: org.jboss.system.server.profileservice.repository.SerializableDeploymentRepository@e1d5d9(root=/Applications/jboss-5.0.1.GA/server, key=org.jboss.profileservice.spi.ProfileKey@143b82c3[domain=default,server=default,name=default])
18:21:30,436 INFO  [ProfileImpl] Using repository:org.jboss.system.server.profileservice.repository.SerializableDeploymentRepository@e1d5d9(root=/Applications/jboss-5.0.1.GA/server, key=org.jboss.profileservice.spi.ProfileKey@143b82c3[domain=default,server=default,name=default])
18:21:30,436 INFO  [ProfileServiceImpl] Loaded profile: ProfileImpl@ae002e{key=org.jboss.profileservice.spi.ProfileKey@143b82c3[domain=default,server=default,name=default]}
18:21:32,935 INFO  [WebService] Using RMI server codebase: http://localhost:8083/
18:21:42,572 INFO  [NativeServerConfig] JBoss Web Services - Stack Native Core
18:21:42,573 INFO  [NativeServerConfig] 3.0.5.GA
18:21:52,836 ERROR [AbstractKernelController] Error installing to ClassLoader: name=vfsfile:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/ state=Describe mode=Manual requiredState=ClassLoader
org.jboss.deployers.spi.DeploymentException: Error creating classloader for vfsfile:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/
    at org.jboss.deployers.spi.DeploymentException.rethrowAsDeploymentException(DeploymentException.java:49)
    at org.jboss.deployers.structure.spi.helpers.AbstractDeploymentContext.createClassLoader(AbstractDeploymentContext.java:576)
    at org.jboss.deployers.structure.spi.helpers.AbstractDeploymentUnit.createClassLoader(AbstractDeploymentUnit.java:159)
    at org.jboss.deployers.spi.deployer.helpers.AbstractClassLoaderDeployer.deploy(AbstractClassLoaderDeployer.java:53)
    at org.jboss.deployers.plugins.deployers.DeployerWrapper.deploy(DeployerWrapper.java:171)
    at org.jboss.deployers.plugins.deployers.DeployersImpl.doDeploy(DeployersImpl.java:1439)
    at org.jboss.deployers.plugins.deployers.DeployersImpl.doInstallParentFirst(DeployersImpl.java:1157)
    at org.jboss.deployers.plugins.deployers.DeployersImpl.install(DeployersImpl.java:1098)
    at org.jboss.dependency.plugins.AbstractControllerContext.install(AbstractControllerContext.java:348)
    at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:1598)
    at org.jboss.dependency.plugins.AbstractController.incrementState(AbstractController.java:934)
    at org.jboss.dependency.plugins.AbstractController.resolveContexts(AbstractController.java:1062)
    at org.jboss.dependency.plugins.AbstractController.resolveContexts(AbstractController.java:984)
    at org.jboss.dependency.plugins.AbstractController.change(AbstractController.java:822)
    at org.jboss.dependency.plugins.AbstractController.change(AbstractController.java:553)
    at org.jboss.deployers.plugins.deployers.DeployersImpl.process(DeployersImpl.java:781)
    at org.jboss.deployers.plugins.main.MainDeployerImpl.process(MainDeployerImpl.java:698)
    at org.jboss.system.server.profileservice.ProfileServiceBootstrap.loadProfile(ProfileServiceBootstrap.java:304)
    at org.jboss.system.server.profileservice.ProfileServiceBootstrap.start(ProfileServiceBootstrap.java:205)
    at org.jboss.bootstrap.AbstractServerImpl.start(AbstractServerImpl.java:405)
    at org.jboss.Main.boot(Main.java:209)
    at org.jboss.Main$1.run(Main.java:547)
    at java.lang.Thread.run(Thread.java:613)
Caused by: java.lang.Error: Error visiting FileHandler@5567366[path=TwitterEAR.ear/TwitterPoCEJB.jar context=file:/Applications/jboss-5.0.1.GA/server/default/deploy/ real=file:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/TwitterPoCEJB.jar/]
    at org.jboss.classloading.plugins.vfs.PackageVisitor.determineAllPackages(PackageVisitor.java:98)
    at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.determineCapabilities(VFSDeploymentClassLoaderPolicyModule.java:108)
    at org.jboss.classloading.spi.dependency.Module.getCapabilities(Module.java:654)
    at org.jboss.classloading.spi.dependency.Module.determinePackageNames(Module.java:713)
    at org.jboss.classloading.spi.dependency.Module.getPackageNames(Module.java:698)
    at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.determinePolicy(VFSDeploymentClassLoaderPolicyModule.java:129)
    at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.determinePolicy(VFSDeploymentClassLoaderPolicyModule.java:48)
    at org.jboss.classloading.spi.dependency.policy.ClassLoaderPolicyModule.getPolicy(ClassLoaderPolicyModule.java:195)
    at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.getPolicy(VFSDeploymentClassLoaderPolicyModule.java:122)
    at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.getPolicy(VFSDeploymentClassLoaderPolicyModule.java:48)
    at org.jboss.classloading.spi.dependency.policy.ClassLoaderPolicyModule.registerClassLoaderPolicy(ClassLoaderPolicyModule.java:131)
    at org.jboss.deployers.plugins.classloading.AbstractLevelClassLoaderSystemDeployer.createClassLoader(AbstractLevelClassLoaderSystemDeployer.java:120)
    at org.jboss.deployers.structure.spi.helpers.AbstractDeploymentContext.createClassLoader(AbstractDeploymentContext.java:562)
    ... 21 more
Caused by: java.lang.RuntimeException: java.util.zip.ZipException: error in opening zip file
    at org.jboss.virtual.plugins.context.AbstractExceptionHandler.handleZipEntriesInitException(AbstractExceptionHandler.java:39)
    at org.jboss.virtual.plugins.context.helpers.NamesExceptionHandler.handleZipEntriesInitException(NamesExceptionHandler.java:63)
    at org.jboss.virtual.plugins.context.zip.ZipEntryContext.ensureEntries(ZipEntryContext.java:610)
    at org.jboss.virtual.plugins.context.zip.ZipEntryContext.checkIfModified(ZipEntryContext.java:757)
    at org.jboss.virtual.plugins.context.zip.ZipEntryContext.getChildren(ZipEntryContext.java:829)
    at org.jboss.virtual.plugins.context.zip.ZipEntryHandler.getChildren(ZipEntryHandler.java:159)
    at org.jboss.virtual.plugins.context.DelegatingHandler.getChildren(DelegatingHandler.java:121)
    at org.jboss.virtual.plugins.context.AbstractVFSContext.getChildren(AbstractVFSContext.java:211)
    at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:328)
    at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:298)
    at org.jboss.virtual.VFS.visit(VFS.java:433)
    at org.jboss.virtual.VirtualFile.visit(VirtualFile.java:437)
    at org.jboss.virtual.VirtualFile.getChildren(VirtualFile.java:386)
    at org.jboss.virtual.VirtualFile.getChildren(VirtualFile.java:367)
    at org.jboss.classloading.plugins.vfs.PackageVisitor.visit(PackageVisitor.java:200)
    at org.jboss.virtual.plugins.vfs.helpers.WrappingVirtualFileHandlerVisitor.visit(WrappingVirtualFileHandlerVisitor.java:62)
    at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:353)
    at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:298)
    at org.jboss.virtual.VFS.visit(VFS.java:433)
    at org.jboss.virtual.VirtualFile.visit(VirtualFile.java:437)
    at org.jboss.classloading.plugins.vfs.PackageVisitor.determineAllPackages(PackageVisitor.java:94)
    ... 33 more
Caused by: java.util.zip.ZipException: error in opening zip file
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.<init>(ZipFile.java:203)
    at java.util.zip.ZipFile.<init>(ZipFile.java:234)
    at org.jboss.virtual.plugins.context.zip.ZipFileWrapper.ensureZipFile(ZipFileWrapper.java:175)
    at org.jboss.virtual.plugins.context.zip.ZipFileWrapper.acquire(ZipFileWrapper.java:245)
    at org.jboss.virtual.plugins.context.zip.ZipEntryContext.initEntries(ZipEntryContext.java:470)
    at org.jboss.virtual.plugins.context.zip.ZipEntryContext.ensureEntries(ZipEntryContext.java:603)
    ... 51 more
18:21:56,772 INFO  [JMXConnectorServerService] JMX Connector server: service:jmx:rmi://localhost/jndi/rmi://localhost:1090/jmxconnector
18:21:56,959 INFO  [MailService] Mail Service bound to java:/Mail
18:21:59,450 WARN  [JBossASSecurityMetadataStore] WARNING! POTENTIAL SECURITY RISK. It has been detected that the MessageSucker component which sucks messages from one node to another has not had its password changed from the installation default. Please see the JBoss Messaging user guide for instructions on how to do this.
18:21:59,489 WARN  [AnnotationCreator] No ClassLoader provided, using TCCL: org.jboss.managed.api.annotation.ManagementComponent
18:21:59,789 INFO  [TransactionManagerService] JBossTS Transaction Service (JTA version) - JBoss Inc.
18:21:59,789 INFO  [TransactionManagerService] Setting up property manager MBean and JMX layer
18:22:00,040 INFO  [TransactionManagerService] Initializing recovery manager
18:22:00,160 INFO  [TransactionManagerService] Recovery manager configured
18:22:00,160 INFO  [TransactionManagerService] Binding TransactionManager JNDI Reference
18:22:00,184 INFO  [TransactionManagerService] Starting transaction recovery manager
18:22:01,243 INFO  [Http11Protocol] Initializing Coyote HTTP/1.1 on http-localhost%2F127.0.0.1-8080
18:22:01,244 INFO  [AjpProtocol] Initializing Coyote AJP/1.3 on ajp-localhost%2F127.0.0.1-8009
18:22:01,244 INFO  [StandardService] Starting service jboss.web
18:22:01,247 INFO  [StandardEngine] Starting Servlet Engine: JBoss Web/2.1.2.GA
18:22:01,336 INFO  [Catalina] Server startup in 161 ms
18:22:01,360 INFO  [TomcatDeployment] deploy, ctxPath=/invoker
18:22:02,014 INFO  [TomcatDeployment] deploy, ctxPath=/web-console
18:22:02,459 INFO  [TomcatDeployment] deploy, ctxPath=/jbossws
18:22:02,570 INFO  [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/jboss-local-jdbc.rar/META-INF/ra.xml
18:22:02,586 INFO  [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/jboss-xa-jdbc.rar/META-INF/ra.xml
18:22:02,645 INFO  [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/jms-ra.rar/META-INF/ra.xml
18:22:02,663 INFO  [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/mail-ra.rar/META-INF/ra.xml
18:22:02,705 INFO  [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/quartz-ra.rar/META-INF/ra.xml
18:22:02,801 INFO  [SimpleThreadPool] Job execution threads will use class loader of thread: main
18:22:02,850 INFO  [QuartzScheduler] Quartz Scheduler v.1.5.2 created.
18:22:02,857 INFO  [RAMJobStore] RAMJobStore initialized.
18:22:02,858 INFO  [StdSchedulerFactory] Quartz scheduler 'DefaultQuartzScheduler' initialized from default resource file in Quartz package: 'quartz.properties'
18:22:02,858 INFO  [StdSchedulerFactory] Quartz scheduler version: 1.5.2
18:22:02,859 INFO  [QuartzScheduler] Scheduler DefaultQuartzScheduler_$_NON_CLUSTERED started.
18:22:03,888 INFO  [ConnectionFactoryBindingService] Bound ConnectionManager 'jboss.jca:service=DataSourceBinding,name=DefaultDS' to JNDI name 'java:DefaultDS'
18:22:04,530 INFO  [ServerPeer] JBoss Messaging 1.4.1.GA server [0] started
18:22:04,624 INFO  [QueueService] Queue[/queue/DLQ] started, fullSize=200000, pageSize=2000, downCacheSize=2000
18:22:04,632 WARN  [ConnectionFactoryJNDIMapper] supportsFailover attribute is true on connection factory: jboss.messaging.connectionfactory:service=ClusteredConnectionFactory but post office is non clustered. So connection factory will *not* support failover
18:22:04,632 WARN  [ConnectionFactoryJNDIMapper] supportsLoadBalancing attribute is true on connection factory: jboss.messaging.connectionfactory:service=ClusteredConnectionFactory but post office is non clustered. So connection factory will *not* support load balancing
18:22:04,742 INFO  [ConnectionFactory] Connector bisocket://localhost:4457 has leasing enabled, lease period 10000 milliseconds
18:22:04,742 INFO  [ConnectionFactory] org.jboss.jms.server.connectionfactory.ConnectionFactory@6af9ad started
18:22:04,746 INFO  [QueueService] Queue[/queue/ExpiryQueue] started, fullSize=200000, pageSize=2000, downCacheSize=2000
18:22:04,747 INFO  [ConnectionFactory] Connector bisocket://localhost:4457 has leasing enabled, lease period 10000 milliseconds
18:22:04,747 INFO  [ConnectionFactory] org.jboss.jms.server.connectionfactory.ConnectionFactory@5ac953 started
18:22:04,750 INFO  [ConnectionFactory] Connector bisocket://localhost:4457 has leasing enabled, lease period 10000 milliseconds
18:22:04,750 INFO  [ConnectionFactory] org.jboss.jms.server.connectionfactory.ConnectionFactory@e8fa3a started
18:22:05,050 INFO  [ConnectionFactoryBindingService] Bound ConnectionManager 'jboss.jca:service=ConnectionFactoryBinding,name=JmsXA' to JNDI name 'java:JmsXA'
18:22:05,073 INFO  [TomcatDeployment] deploy, ctxPath=/
18:22:05,178 INFO  [TomcatDeployment] deploy, ctxPath=/jmx-console
18:22:05,290 ERROR [ProfileServiceBootstrap] Failed to load profile: Summary of incomplete deployments (SEE PREVIOUS ERRORS FOR DETAILS):

DEPLOYMENTS IN ERROR:
  Deployment "vfsfile:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/" is in error due to the following reason(s): java.util.zip.ZipException: error in opening zip file

18:22:05,301 INFO  [Http11Protocol] Starting Coyote HTTP/1.1 on http-localhost%2F127.0.0.1-8080
18:22:05,364 INFO  [AjpProtocol] Starting Coyote AJP/1.3 on ajp-localhost%2F127.0.0.1-8009
18:22:05,373 INFO  [ServerImpl] JBoss (Microcontainer) [5.0.1.GA (build: SVNTag=JBoss_5_0_1_GA date=200902231221)] Started in 43s:467ms

The mentioned ear and war file are both in the deploy directory.

Does anybody have hints?