I assume you're using the steps from the following document to configure glassfish plugin.
https://glassfishplugins.dev.java.net/eclipse33/
After you click at the "Download additional server adapters" link, please wait for a while, you might not see anything at first, but after a few minutes "Glassfish Java EE 5 Server" entry would come up. Please, see the 2 attached files for the "install new adapter" process.
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