From: <glassfish_at_javadesktop.org>
Date: Thu, 04 Feb 2010 06:19:20 PST

The problem was not with Toplink or the SQL-Server, the problem was the Netbeans autogenerated Java application, extending the org.jdesktop.application.SingleFrameApplication.
You have to call: ProxySelector.getDefault(); in your main method before launch(...);

See e.g. http://72.5.124.102/thread.jspa?messageID=10349206

The tutorial was recently "reprinted"(http://platform.netbeans.org/tutorials/nbm-crud.html), perhaps this "magic spell" helps someone.
[Message sent by forum member 'jiai' (jessica_at_pccsxb.net)]

http://forums.java.net/jive/thread.jspa?messageID=384781