managedconnectionfactory is null

"You are trying to use a connection factory that has been shut down: ManagedConnectionFactory is null."

whenever the i save something on my IDE and hot deployment is done.

The fix for the above error is change overwrite="true" to overwrite="false"

<target name="datasource">
<fail unless="jboss.home">jboss.home not set</fail>
<copy file="${basedir}/resources/${project.name}-${profile}-ds.xml"
tofile="${deploy.dir}/${project.name}-ds.xml"
overwrite="false"/>
</target>


as shown above in your build.xml file

I have the same problem, when test seaminaction golftip sample application.