Authenticator valve at the host level, not possible?

[Thomas . Gaudin]

Hi,

I am trying to implement my own authentication system (extending 
AuthenticatorBase).
I would like this valve to be set up at the host level so my server.xml, 
looks like

<Host name="localhost" debug="0" appBase="webapps"  unpackWARs="true" 
autoDeploy="true">
        <Context path="/myContext" docBase="ina" debug="0">
                        <Manager 
classname="org.apache.catalina.session.StandardManager" pathname="" />
                        <Logger 
className="org.apache.catalina.logger.FileLogger" directory="logs" 
prefix="myLog." suffix=".log" timestamp="true"/>
                </Context>
        <Logger className="org.apache.catalina.logger.FileLogger" 
directory="logs"  prefix="localhost_log." suffix=".txt" timestamp="true"/>
                <Valve className="com.mycompany.MyAuthenticator" 
debug="10" myParam1="p1" myParam2="p2"/>
</Host>

When I try to start my tomcat, it crashes at startup with the following : 

....
Catalina.start: java.lang.IllegalArgumentException: Configuration error: 
Must be attached to a Context
java.lang.IllegalArgumentException: Configuration error:  Must be attached 
to a Context
        at 
org.apache.commons.digester.Digester.createSAXException(Digester.java:2540)
        at 
org.apache.commons.digester.Digester.createSAXException(Digester.java:2566)
        at 
org.apache.commons.digester.Digester.endElement(Digester.java:1061)
        at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown 
Source)
        at 
org.apache.xerces.parsers.AbstractXMLDocumentParser.emptyElement(Unknown 
Source)
        at 
org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown 
Source)
        at 
org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown
 
Source)
        at 
org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown 
Source)
        at org.apache.xerces.parsers.XML11Configuration.parse(Unknown 
Source)
        at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown 
Source)
        at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
        at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown 
Source)
        at org.apache.commons.digester.Digester.parse(Digester.java:1548)
        at org.apache.catalina.startup.Catalina.start(Catalina.java:449)
        at org.apache.catalina.startup.Catalina.execute(Catalina.java:400)
        at org.apache.catalina.startup.Catalina.process(Catalina.java:180)
        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:324)
        at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:203)

First question : Am I trying to do it in the bad way?
Second question : What can be the reason why it crashes when I attach my 
valve to the host but starts normally when I attach it to the context?

Thanks for giving opinions.

PS : any link to information related to custom authentication in tomcat is 
welcome!!!

Cheers,


Thomas