This is a quick post i am putting in just because there is so little glassfish info and putting questions on the java glassfish forums will yield as much information as writing the question on a napkin and throwing it down an alley...

I am running glassfish Edition 3.1 (build 43) on linux.  I was getting an odd, Context is already active error when i would try and run an application that i had running on my windows install of glassfish.  The application was built with netbeans 7.0.1.  It was running flawlessly on windows/glassfish.  I tried everything to get the app to load on linux..  The only solution i found was to remove the beans.xml file...  Removing the beans.xml file fixed everything.. I wish that I would have found this sooner.

 I don't know why this worked but it did...  Thank god!  I hope this post saves someone some hair.  Long Live Glassfish!

UPDATE

The above fix was not working either.... Jsf needs that beans.xml to do certain things...  I had to create a seperate glasssfish sever to host the jsf app. Very frustrating... 

You can follow the post here: http://www.java.net/forum/topic/glassfish/glassfish/glassfish-server-context-already-active-when-trying-host-multiple-jsf-applications

Just a warning though, unlike the other large companies, Oracle does not do much posting on their forums...  Glassfish has been a bit of a mess since Oracle has taken over.  Lets hope they don't ruin MySQL as well.

UPDATE 2

i was running glassfish version 3.0.1...  Upgrading to glassfish 3.1.1 and we are no longer having the problem.   For those that want to upgrade glassfish via the command line you have to run the following from the directory where you run your asadmin; /opt/glassfish3/bin# dbus-launch --exit-with-session ./pkg image-update 

i had to include the dbus-launch command because i was getting this error:  GConf Error: Failed to contact configuration server; some possible causes are that you need to enable TCP/IP networking for ORBit, or you have stale NFS locks due to a system crash. See http://projects.gnome.org/gconf/ for information. (Details -  1: Not running within active session)