You can get the demo app here:
https://repository.apache.org/content/repositories/orgapachemyfaces-013/org/apache/myfaces/trinidad/trinidad-demo/1.2.14/trinidad-demo-1.2.14.war

You will see the error below on AS6 Final. This works on AS5.1 and it reportedly also works on Tomcat 7.

There is a similar issue here: https://issues.apache.org/jira/browse/TOMAHAWK-1560. I assume that one can be worked around by setting in war-deployers-jboss-beans.xml:
<bean name="TldParsingDeployer" class="org.jboss.deployment.TldParsingDeployer">
<property name="relativeOrder">2002</property>
<property name="useSchemaValidation">false</property>
<property name="useValidation">false</property>
</bean>

But even with no validation, you still get this error for the trinidad demo:

10:27:01,762 WARN [JBossEntityResolver] Trying to resolve systemId as a non-fil
e URL: http://java.sun.com/xml/ns/javaee
10:28:02,379 ERROR [AbstractKernelController] Error installing to Parse: name=vf
s:///C:/jboss-6.0.0.Final/server/default/deploy/trinidad-demo-1.2.14.war state=P
reParse mode=Manual requiredState=Parse: org.jboss.deployers.spi.DeploymentExcep
tion: Error creating managed object for vfs:///C:/jboss-6.0.0.Final/server/defau
lt/deploy/trinidad-demo-1.2.14.war
at org.jboss.deployers.spi.DeploymentException.rethrowAsDeploymentExcept
ion(DeploymentException.java:49) [:2.2.0.GA]
at org.jboss.deployers.spi.deployer.helpers.AbstractParsingDeployerWithO
utput.createMetaData(AbstractParsingDeployerWithOutput.java:383) [:2.2.0.GA]
at org.jboss.deployers.spi.deployer.helpers.AbstractParsingDeployerWithO
utput.createMetaData(AbstractParsingDeployerWithOutput.java:343) [:2.2.0.GA]
at org.jboss.deployers.spi.deployer.helpers.AbstractParsingDeployerWithO
utput.createMetaData(AbstractParsingDeployerWithOutput.java:315) [:2.2.0.GA]
at org.jboss.deployers.spi.deployer.helpers.AbstractParsingDeployerWithO
utput.deploy(AbstractParsingDeployerWithOutput.java:255) [:2.2.0.GA]
at org.jboss.deployers.plugins.deployers.DeployerWrapper.deploy(Deployer
Wrapper.java:179) [:2.2.0.GA]
at org.jboss.deployers.plugins.deployers.DeployersImpl.doDeploy(Deployer
sImpl.java:1832) [:2.2.0.GA]
at org.jboss.deployers.plugins.deployers.DeployersImpl.doInstallParentFi
rst(DeployersImpl.java:1550) [:2.2.0.GA]
at org.jboss.deployers.plugins.deployers.DeployersImpl.install(Deployers
Impl.java:1491) [:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractControllerContext.install(Abstra
ctControllerContext.java:379) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.install(AbstractContr
oller.java:2044) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.incrementState(Abstra
ctController.java:1083) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.executeOrIncrementSta
teDirectly(AbstractController.java:1322) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.resolveContexts(Abstr
actController.java:1246) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.resolveContexts(Abstr
actController.java:1139) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.change(AbstractContro
ller.java:939) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.change(AbstractContro
ller.java:654) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.deployers.plugins.deployers.DeployersImpl.change(DeployersI
mpl.java:1983) [:2.2.0.GA]
at org.jboss.deployers.plugins.deployers.DeployersImpl.process(Deployers
Impl.java:1076) [:2.2.0.GA]
at org.jboss.deployers.plugins.main.MainDeployerImpl.process(MainDeploye
rImpl.java:679) [:2.2.0.GA]
at org.jboss.system.server.profileservice.deployers.MainDeployerPlugin.p
rocess(MainDeployerPlugin.java:106) [:6.0.0.Final]
at org.jboss.profileservice.dependency.ProfileControllerContext$Delegate
Deployer.process(ProfileControllerContext.java:143) [:0.2.2]
at org.jboss.profileservice.dependency.ProfileDeployAction.deploy(Profil
eDeployAction.java:151) [:0.2.2]
at org.jboss.profileservice.dependency.ProfileDeployAction.installAction
Internal(ProfileDeployAction.java:94) [:0.2.2]
at org.jboss.kernel.plugins.dependency.InstallsAwareAction.installAction
(InstallsAwareAction.java:54) [jboss-kernel.jar:2.2.0.GA]
at org.jboss.kernel.plugins.dependency.InstallsAwareAction.installAction
(InstallsAwareAction.java:42) [jboss-kernel.jar:2.2.0.GA]
at org.jboss.dependency.plugins.action.SimpleControllerContextAction.sim
pleInstallAction(SimpleControllerContextAction.java:62) [jboss-dependency.jar:2.
2.0.GA]
at org.jboss.dependency.plugins.action.AccessControllerContextAction.ins
tall(AccessControllerContextAction.java:71) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractControllerContextActions.install
(AbstractControllerContextActions.java:51) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractControllerContext.install(Abstra
ctControllerContext.java:379) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.install(AbstractContr
oller.java:2044) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.incrementState(Abstra
ctController.java:1083) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.executeOrIncrementSta
teDirectly(AbstractController.java:1322) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.resolveContexts(Abstr
actController.java:1246) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.resolveContexts(Abstr
actController.java:1139) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.change(AbstractContro
ller.java:939) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.dependency.plugins.AbstractController.change(AbstractContro
ller.java:654) [jboss-dependency.jar:2.2.0.GA]
at org.jboss.profileservice.dependency.ProfileActivationWrapper$BasicPro
fileActivation.start(ProfileActivationWrapper.java:190) [:0.2.2]
at org.jboss.profileservice.dependency.ProfileActivationWrapper.start(Pr
ofileActivationWrapper.java:87) [:0.2.2]
at org.jboss.profileservice.dependency.ProfileActivationService.activate
Profile(ProfileActivationService.java:215) [:0.2.2]
at org.jboss.profileservice.dependency.ProfileActivationService.activate
(ProfileActivationService.java:159) [:0.2.2]
at org.jboss.profileservice.bootstrap.AbstractProfileServiceBootstrap.ac
tivate(AbstractProfileServiceBootstrap.java:112) [:0.2.2]
at org.jboss.profileservice.resolver.BasicResolverFactory$ProfileResolve
rFacade.deploy(BasicResolverFactory.java:87) [:0.2.2]
at org.jboss.profileservice.bootstrap.AbstractProfileServiceBootstrap.st
art(AbstractProfileServiceBootstrap.java:91) [:0.2.2]
at org.jboss.system.server.profileservice.bootstrap.BasicProfileServiceB
ootstrap.start(BasicProfileServiceBootstrap.java:132) [:6.0.0.Final]
at org.jboss.system.server.profileservice.bootstrap.BasicProfileServiceB
ootstrap.start(BasicProfileServiceBootstrap.java:56) [:6.0.0.Final]
at org.jboss.bootstrap.impl.base.server.AbstractServer.startBootstraps(A
bstractServer.java:827) [jboss-bootstrap-impl-base.jar:2.1.0-alpha-5]
at org.jboss.bootstrap.impl.base.server.AbstractServer$StartServerTask.r
un(AbstractServer.java:417) [jboss-bootstrap-impl-base.jar:2.1.0-alpha-5]
at java.lang.Thread.run(Thread.java:619) [:1.6.0_18]
Caused by: org.jboss.xb.binding.JBossXBException: Failed to parse source: vfs://
/C:/jboss-6.0.0.Final/server/default/deploy/trinidad-demo-1.2.14.war/WEB-INF/lib
/trinidad-impl-1.2.14.jar/META-INF/tr.tld@1,238
at org.jboss.xb.binding.parser.sax.SaxJBossXBParser.parse(SaxJBossXBPars
er.java:224) [jbossxb.jar:2.0.3.GA]
at org.jboss.xb.binding.UnmarshallerImpl.unmarshal(UnmarshallerImpl.java
:178) [jbossxb.jar:2.0.3.GA]
at org.jboss.xb.util.JBossXBHelper.parse(JBossXBHelper.java:257) [jbossx
b.jar:2.0.3.GA]
at org.jboss.xb.util.JBossXBHelper.parse(JBossXBHelper.java:231) [jbossx
b.jar:2.0.3.GA]
at org.jboss.deployers.vfs.spi.deployer.SchemaResolverDeployer.parse(Sch
emaResolverDeployer.java:137) [:2.2.0.GA]
at org.jboss.deployment.TldParsingDeployer.parse(TldParsingDeployer.java
:64) [:6.0.0.Final]
at org.jboss.deployment.TldParsingDeployer.parse(TldParsingDeployer.java
:38) [:6.0.0.Final]
at org.jboss.deployers.vfs.spi.deployer.SchemaResolverDeployer.parse(Sch
emaResolverDeployer.java:121) [:2.2.0.GA]
at org.jboss.deployers.vfs.spi.deployer.AbstractVFSParsingDeployer.handl
eMultipleFiles(AbstractVFSParsingDeployer.java:446) [:2.2.0.GA]
at org.jboss.deployers.vfs.spi.deployer.AbstractVFSParsingDeployer.parse
(AbstractVFSParsingDeployer.java:319) [:2.2.0.GA]
at org.jboss.deployers.spi.deployer.helpers.AbstractParsingDeployerWithO
utput.createMetaData(AbstractParsingDeployerWithOutput.java:376) [:2.2.0.GA]
... 47 more
Caused by: org.jboss.xb.binding.JBossXBRuntimeException: Failed to parse schema
for nsURI=http://java.sun.com/xml/ns/javaee, localName=taglib, schemaLocation=nu
ll
at org.jboss.xb.binding.resolver.AbstractMutableSchemaResolver.resolve(A
bstractMutableSchemaResolver.java:350) [jbossxb.jar:2.0.3.GA]
at org.jboss.xb.binding.sunday.unmarshalling.SundayContentHandler.startE
lement(SundayContentHandler.java:176) [jbossxb.jar:2.0.3.GA]
at org.jboss.xb.binding.parser.sax.SaxJBossXBParser.startElement(SaxJBos
sXBParser.java:401) [jbossxb.jar:2.0.3.GA]
at org.apache.xerces.parsers.AbstractSAXParser.startElement(Unknown Sour
ce) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.impl.xs.XMLSchemaValidator.startElement(Unknown Sou
rce) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.xinclude.XIncludeHandler.startElement(Unknown Sourc
e) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unkn
own Source) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.impl.XMLNSDocumentScannerImpl$NSContentDispatcher.s
canRootElementHook(Unknown Source) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContent
Dispatcher.dispatch(Unknown Source) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Un
known Source) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) [x
ercesImpl.jar:6.0.0.Final]
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) [x
ercesImpl.jar:6.0.0.Final]
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source) [xercesImpl
.jar:6.0.0.Final]
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source) [xe
rcesImpl.jar:6.0.0.Final]
at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Sour
ce) [xercesImpl.jar:6.0.0.Final]
at org.jboss.xb.binding.parser.sax.SaxJBossXBParser.parse(SaxJBossXBPars
er.java:209) [jbossxb.jar:2.0.3.GA]
... 57 more
Caused by: org.jboss.xb.binding.JBossXBRuntimeException: -1:-1 -1:-1 schema_refe
rence.4: Failed to read schema document 'null', because 1) could not find the do
cument; 2) the document could not be read; 3) the root element of the document i
s not <xsd:schema>.
at org.jboss.xb.binding.sunday.unmarshalling.XsdBinderTerminatingErrorHa
ndler.handleError(XsdBinderTerminatingErrorHandler.java:40) [jbossxb.jar:2.0.3.G
A]
at org.apache.xerces.impl.xs.XMLSchemaLoader.reportDOMFatalError(Unknown
Source) [xercesImpl.jar:6.0.0.Final]
at org.apache.xerces.impl.xs.XSLoaderImpl.load(Unknown Source) [xercesIm
pl.jar:6.0.0.Final]
at org.jboss.xb.binding.Util.loadSchema(Util.java:394) [jbossxb.jar:2.0.
3.GA]
at org.jboss.xb.binding.sunday.unmarshalling.XsdBinder.bind(XsdBinder.ja
va:178) [jbossxb.jar:2.0.3.GA]
at org.jboss.xb.binding.sunday.unmarshalling.XsdBinder.bind(XsdBinder.ja
va:149) [jbossxb.jar:2.0.3.GA]
at org.jboss.xb.binding.resolver.AbstractMutableSchemaResolver.resolve(A
bstractMutableSchemaResolver.java:342) [jbossxb.jar:2.0.3.GA]
... 72 more