Hi, I already had this error in the past (with Struts 2.1.8 and Jboss 6.0.0 M1). And I know there is a JIRA issue about it : https://issues.apache.org/jira/browse/WW-3299
And I already asked about this error in the past. I fixed it by extracting the struts-tag.tld file from the library struts2-core-2.1.8.1.jar and modifying the tlib version by shortening it like this : <tlib-version>2.2.3</tlib-version> ==> <tlib-version>2.2</tlib-version> I then reconstructed the library struts2-core-2.1.8.1.jar with the modified struts-tag.tld file. But i also get tons of errors regarding the <display-name> and <description> tags. For instance : <display-name>"Struts Tags"</display-name> <description><![CDATA[Execute an action from within a view]]></description> It seems i now also need to remove these 2 tags (hundreds of lines in the TLD file). Isn't there a quick fix for it ? I always waste a lot of time fixing this versioning problem when i set up a new environment with Jboss and Struts 2. Thanks for helping. Here is a part of the stacktrace when i try to deploy the webapp: Caused by: org.jboss.xb.binding.JBossXBException: Failed to parse source: cvc-datatype-valid.1.2.1: '2.2.3' is not a valid value for 'decimal'. @ vfs:///K:/jboss-6.0.0.20100429-M3/server/default/deploy/Chapitre1.war/WEB-INF/lib/struts2-core-2.1.8.1.jar/META-INF/struts-tags.tld[9,37] at org.jboss.xb.binding.parser.sax.SaxJBossXBParser.parse(SaxJBossXBParser.java:195) [jbossxb.jar:2.0.2.Beta7] at org.jboss.xb.binding.UnmarshallerImpl.unmarshal(UnmarshallerImpl.java:168) [jbossxb.jar:2.0.2.Beta7] at org.jboss.xb.util.JBossXBHelper.parse(JBossXBHelper.java:229) [jbossxb.jar:2.0.2.Beta7] at org.jboss.xb.util.JBossXBHelper.parse(JBossXBHelper.java:206) [jbossxb.jar:2.0.2.Beta7] at org.jboss.deployers.vfs.spi.deployer.SchemaResolverDeployer.parse(SchemaResolverDeployer.java:137) [:2.2.0.Alpha4] at org.jboss.deployment.TldParsingDeployer.parse(TldParsingDeployer.java:64) [:6.0.0.20100429-M3] at org.jboss.deployment.TldParsingDeployer.parse(TldParsingDeployer.java:38) [:6.0.0.20100429-M3] at org.jboss.deployers.vfs.spi.deployer.SchemaResolverDeployer.parse(SchemaResolverDeployer.java:121) [:2.2.0.Alpha4] at org.jboss.deployers.vfs.spi.deployer.AbstractVFSParsingDeployer.parseAndInit(AbstractVFSParsingDeployer.java:315) [:2.2.0.Alpha4] at org.jboss.deployers.vfs.spi.deployer.AbstractVFSParsingDeployer.parse(AbstractVFSParsingDeployer.java:280) [:2.2.0.Alpha4] at org.jboss.deployers.spi.deployer.helpers.AbstractParsingDeployerWithOutput.createMetaData(AbstractParsingDeployerWithOutput.java:355) [:2.2.0.Alpha4] ... 36 more Caused by: org.xml.sax.SAXException: cvc-datatype-valid.1.2.1: '2.2.3' is not a valid value for 'decimal'. @ vfs:///K:/jboss-6.0.0.20100429-M3/server/default/deploy/Chapitre1.war/WEB-INF/lib/struts2-core-2.1.8.1.jar/META-INF/struts-tags.tld[9,37]