I'm doing Struts 2 development with Glassfish v2. It definitely works and I haven't had to do anything special to get it working.
I have no idea why you are getting 404 errors with *.action URLs. They work fine for me. Often, when there is a server error, the real issue is recorded in a log file, and the client web browser shows a 404 page (which is very misleading, IMO). Is *.action properly mapped in web.xml? Otherwise, I bet there is an error in your server logs.
I also followed the link you posted. I use the exact same taglib in my jsp files and it worked on the first try... I'm not sure what could be wrong.
Overall, getting Glassfish v2 working with Struts 2 was pretty painless for me. I'd be happy to help you diagnose your issue, however, the symptom you describe is too generic. If you could identify and post the underlying error from your log files, that would help.
Alternatively, if that doesn't help, I could create a HelloWorld Struts2 app in NetBeans and zip and attach that project if that would get you started.
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