"Too many open files error" when running TestNG in Eclipse

I frequently get this exception when trying to run a test from TestNG in Eclipse.

Open a terminal and write ulimit -n and you will most probably get 1024.
(ulimit -a) for everything. (I am running Ubuntu 9.10)

This means you can have max 1024 open files.

To fix this check this page out and follow the instructions.
http://knol.google.com/k/fred-grott/open-file-limits-settings-on-ubuntu/166jfml0mowlh/3#

setProperty must be overridden by all subclasses of SOAPMessage

Have you gotten this error message? Then you probably either upgraded from Java 5 to Java 6 in JBoss application, or you just tried to run your webservice client for the first time.

The reason your Webservice client call suddenly fails is because of a bug in JBoss WS with JBoss 4.x

I haven't tested this on JBoss 5, so I cannot for sure exclude this bug in JBoss 5. However, the bug seem to be fixed in jbossws-2.0.

The solution to this problem is to

Copy the three jars from <JBOSS_HOME>\server\default\lib to <JBOSS_HOME>\lib\endorsed.

jboss-jaxrpc.jar
jboss-jaxws.jar
jboss-saaj.jar 

More information can be found here