Using the following context.xml

<Context cookies="true" crossContext="true">
<Manager className="org.apache.catalina.session.PersistentManager" maxIdleSwap="1200" saveOnRestart="true">
<Store checkInterval="60" className="org.apache.catalina.session.JDBCStore" connectionURL="jdbc:mysql://localhost:3306/XXX?user=XXX&password=XXX" driverName="com.mysql.jdbc.Driver" sessionAppCol="app_name" sessionDataCol="session_data" sessionIdCol="session_id" sessionLastAccessedCol="last_access" sessionMaxInactiveCol="max_inactive" sessionTable="tomcat_sessions" sessionValidCol="valid_session"/>
</Manager>
<InstanceListener>org.jboss.web.tomcat.security.RunAsListener</InstanceListener>
</Context>

That used to work in jboss4.0.5GA and correct according to tomcat 6 documentation jboss 5.1.0GA fails to start tomcat with the following exception:

2009-11-02 23:11:54,292 INFO [org.jboss.web.tomcat.service.deployers.TomcatDeployment] (main) deplo
y, ctxPath=/
2009-11-02 23:11:55,619 ERROR [org.jboss.web.tomcat.service.deployers.JBossContextConfig] (main) XML
error parsing: context.xml
org.jboss.xb.binding.JBossXBException: Failed to parse source: Store not found as a child of Manager
in unordered_sequence: attributes?
at org.jboss.xb.binding.parser.sax.SaxJBossXBParser.parse(SaxJBossXBParser.java:203)
at org.jboss.xb.binding.parser.sax.SaxJBossXBParser.parse(SaxJBossXBParser.java:183)
at org.jboss.xb.binding.UnmarshallerImpl.unmarshal(UnmarshallerImpl.java:133)
at org.jboss.web.tomcat.service.deployers.JBossContextConfig.processContextConfig(JBossContextCo
nfig.java:573)
at org.jboss.web.tomcat.service.deployers.JBossContextConfig.init(JBossContextConfig.java:536)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:279)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
at org.apache.catalina.core.StandardContext.init(StandardContext.java:5436)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4148)
at org.jboss.web.tomcat.service.deployers.TomcatDeployment.performDeployInternal(TomcatDeploymen
t.java:310)
at org.jboss.web.tomcat.service.deployers.TomcatDeployment.performDeploy(TomcatDeployment.java:1
42)
at org.jboss.web.deployers.AbstractWarDeployment.start(AbstractWarDeployment.java:461)
at org.jboss.web.deployers.WebModule.startModule(WebModule.java:118)
at org.jboss.web.deployers.WebModule.start(WebModule.java:97)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:157)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:96)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:668)
at org.jboss.system.microcontainer.ServiceProxy.invoke(ServiceProxy.java:206)
at $Proxy38.start(Unknown Source)

I opened a thread in the tomcat integration forum (http://www.jboss.org/index.html?module=bb&op=viewtopic&t=163337) but got no response.