Which app server are you using? Looks like you are not using glassfish, because we don't use packages like com.iplanet.ias.web.jsp.*
The old appserver invokes jspc in a separate process, but in glassfish, javac is invoked with JSR199 api's, in the same JVM. Can you try you application in glassfish? I suspect that this would not be an issue in glassfish.
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