If you can share your web application with us, I can look into the slow compilation issue, as well as deployment with precompile option issue. Thanks.
Jetty's JSP engine is based on Glassfish V2. One of the changes made in V3 is that ResouceInjector has a new package name: org.glassfish.jsp.api. Therefore JSP files compiled with Jetty cannot be executed in V3.
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