Setting "delegate" to "false" would not be sufficient in this case, because the resolution of classes in certain packages, including those starting with "javax.*", is delegated unconditionally. You would also need to set "useMyFaces" to "true" in your sun-web.xml, as follows:
<sun-web-app >
<class-loader delegate="false"/>
<property name="useMyFaces" value="true"/>
</sun-web-app>
Note that starting with GlassFish v3, we've renamed "useMyFaces" to the more appropriate "useBundledJsf" (but still support the old name).
See also
http://blogs.sun.com/theaquarium/entry/how_to_use_myfaces_with
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