I have run a test for our JBossMQ using JBoss 3.0.3, Red Hat Linux 8.0 and J2SDK 1.4.1_01. The test consist of bursting JBossMQ with 1000 messages. Around 400th or 600th message we have experienced dropped messages. And the last error we encountered is: java.net.SocketException(Too many open files) and I don't know what files are being opened that should be closed. Now, is this a natural JBossMQ behavior? or there is something we forgot to configure?
Try checking which persistance manager you are using. (in jbossmq-service.xml) Probably set to file which generates files in jboss/db/jbossmq/file.
There is a way to increase the limit in the forums elsewhere.