We are running Jboss 3.0.3/Jetty-JDK1.4.1 on a Sun box. The system would mysteriously hang after a seemingly random amount of time. After much trial and error we were able to determine that after the console outputs about 150k of messages the system would hang. Ran this test three times and each time produced the same results. Realizing that we could not account for this oddity we started piping the output to a file. The system is apparently running fine now.
We were not able to reproduce this running the application on Win2K or Redhat Linux.
This seems to be related to the Unix shell you're using, so it would nothing to do with JBoss.
Out of curiosity what shell are running your process in ? csh, bash, ...?
It doesn't really matter because you adopted to correct solution, you want to redirect console output to a log file anyway.