出现以下错误的原因是什么？如何解决？
10:54:14,546 INFO [org.jboss.as.server.deployment] (MSC service thread 1-7) JBAS015876: Starting deployment of "oneflexi.ear"
10:54:14,998 INFO [org.jboss.as.server.deployment] (MSC service thread 1-3) JBAS015876: Starting deployment of "LinkWEB.war"
10:54:14,998 INFO [org.jboss.as.server.deployment] (MSC service thread 1-1) JBAS015876: Starting deployment of "LinkEJB.jar"
10:54:15,225 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-4) MSC00001: Failed to start service jboss.deployment.subunit."oneflexi.ear"."LinkWEB.war".PARSE: org.jboss.msc.service.StartException in service jboss.deployment.subunit."oneflexi.ear"."LinkWEB.war".PARSE: Failed to process phase PARSE of subdeployment "LinkWEB.war" of deployment "oneflexi.ear"
at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:119) [jboss-as-server-7.1.1.Final.jar:7.1.1.Final]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_15]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_15]
at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_15]
Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: JBAS018014: Failed to parse XML descriptor "/content/oneflexi.ear/LinkWEB.war/WEB-INF/jboss-web.xml" at [4,1]
at org.jboss.as.web.deployment.JBossWebParsingDeploymentProcessor.deploy(JBossWebParsingDeploymentProcessor.java:77)
at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:113) [jboss-as-server-7.1.1.Final.jar:7.1.1.Final]
... 5 more
Caused by: javax.xml.stream.XMLStreamException: ParseError at [row,col]:[4,1]
Message: Unexpected element 'error-page' encountered
at org.jboss.metadata.parser.util.MetaDataElementParser.unexpectedElement(MetaDataElementParser.java:108)
at org.jboss.metadata.parser.jbossweb.JBossWebMetaDataParser.parse(JBossWebMetaDataParser.java:211)
at org.jboss.as.web.deployment.JBossWebParsingDeploymentProcessor.deploy(JBossWebParsingDeploymentProcessor.java:69)
... 6 more
10:54:15,266 INFO [org.jboss.as] (MSC service thread 1-5) JBAS015951: Admin console listening on http://127.0.0.1:9990
10:54:15,267 ERROR [org.jboss.as] (MSC service thread 1-5) JBAS015875: JBoss AS 7.1.1.Final "Brontes" started (with errors) in 2477ms - Started 145 of 223 services (3 services failed or missing dependencies, 74 services are passive or on-demand)
10:54:15,469 INFO [org.jboss.as.server] (DeploymentScanner-threads - 2) JBAS015870: Deploy of deployment "oneflexi.ear" was rolled back with failure message {"JBAS014671: Failed services" => {"jboss.deployment.subunit.\"oneflexi.ear\".\"LinkWEB.war\".PARSE" => "org.jboss.msc.service.StartException in service jboss.deployment.subunit.\"oneflexi.ear\".\"LinkWEB.war\".PARSE: Failed to process phase PARSE of subdeployment \"LinkWEB.war\" of deployment \"oneflexi.ear\""}}
10:54:15,478 INFO [org.jboss.as.server.deployment] (MSC service thread 1-8) JBAS015877: Stopped deployment LinkEJB.jar in 8ms
10:54:15,485 INFO [org.jboss.as.server.deployment] (MSC service thread 1-8) JBAS015877: Stopped deployment LinkWEB.war in 15ms
10:54:15,490 INFO [org.jboss.as.server.deployment] (MSC service thread 1-8) JBAS015877: Stopped deployment oneflexi.ear in 20ms
10:54:15,491 INFO [org.jboss.as.controller] (DeploymentScanner-threads - 2) JBAS014774: Service status report
JBAS014777: Services which failed to start: service jboss.deployment.subunit."oneflexi.ear"."LinkWEB.war".PARSE: org.jboss.msc.service.StartException in service jboss.deployment.subunit."oneflexi.ear"."LinkWEB.war".PARSE: Failed to process phase PARSE of subdeployment "LinkWEB.war" of deployment "oneflexi.ear"
10:54:15,492 ERROR [org.jboss.as.server.deployment.scanner] (DeploymentScanner-threads - 1) {"JBAS014653: Composite operation failed and was rolled back. Steps that failed:" => {"Operation step-2" => {"JBAS014671: Failed services" => {"jboss.deployment.subunit.\"oneflexi.ear\".\"LinkWEB.war\".PARSE" => "org.jboss.msc.service.StartException in service jboss.deployment.subunit.\"oneflexi.ear\".\"LinkWEB.war\".PARSE: Failed to process phase PARSE of subdeployment \"LinkWEB.war\" of deployment \"oneflexi.ear\""}}}}
^A