I assume you are not using the built-in automatic support in GlassFish for launching Java EE app clients using Java Web Start. (Such an app client should get this support automatically.)
If so this is really a Java Web Start question as opposed to a GlassFish question.
Having said that...
My understanding is that, starting with some release of Java SE 6 (I don't recall exactly which one but it was a while ago), you could specify a javaagent in the java-vm-args setting in the JNLP. But because that is a potential security issue Java Web Start would not honor that setting unless
1. You included an exact copy of the launching JNLP in the main application's JAR file, and
2. The main application's JAR file was signed.
3. The JNLP specified all permissions in the security setting.
I have not seen this in official documentation anywhere and I have never tried it myself, but in private correspondence with a Java Web Start engineering this is what I was told.
Maybe that will help?
- Tim
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