Unable to end the QP0ZSPWT job when shutting down Tomcat

Hopefully someone will be able to help with this issue:

I have installed Tomcat standalone (i.e. not using ASFTomcat) and am having
difficulty getting the spawned job QP0ZSPWT from ending when I end Tomcat.

The start up script (startcatalina400.sh) does something like this:
export -s QIBM_MULTI_THREADED=Y
export  -s JAVA_HOME=/QIBM/ProdData/Java400/jdk14
export  -s CATALINA_HOME=$1
export  -s CATALINA_BASE=$CATALINA_HOME
CP=$CATALINA_HOME/bin/bootstrap.jar:/qibm/ProdData/Java400/jdk14/lib/tools.j
ar:/qibm/ProdData/OS400/jt400/lib/jt400Native.jar
export   -s CLASSPATH=$CP
java -ms256m -Duser.dir="$CATALINA_BASE" -Dcatalina.base="$CATALINA_BASE" -D
catalina.home="$CATALINA_HOME" org.apache.catalina.startup.Bootstrap start

This is executed using something like this in the CL:
CHGVAR &QSHCMD VALUE('cd' |< &TOMCATPATH |< ';bin/startcatalina400.sh' |>
&TOMCATPATH)
SBMJOB CMD(STRQSH CMD(&QSHCMD)) JOB(TOMCATJOB) JOBD(QSYSWRK)

When the web application runs, I get the following four jobs:
TOMCATJOB
QP0ZSPWP
QP0ZSPWT
QZSHSH

My 'stop' tomcat' script (endcatalina400.sh) does something like the
following:
export QIBM_MULTI_THREADED=Y
export -s CATALINA_HOME=$1
export -s CATALINA_BASE=$CATALINA_HOME
CP=$CATALINA_HOME/bin/bootstrap.jar
export -s CLASSPATH=$CP
java -ms64m -Dcatalina.base="$CATALINA_BASE" -Dcatalina.home="$CATALINA_HOME
" org.apache.catalina.startup.Bootstrap stop

and this is executed as follows from the CL:
CHGVAR &QSHCMD VALUE('cd' |< &TOMCATPATH |< ';bin/stopcatalina400.sh' |>
&TOMCATPATH)
SBMJOB CMD(STRQSH CMD(&QSHCMD)) JOB(ENDTOMCATJOB) JOBD(QSYSWRK)


Right now, the 'stop script' is not stopping Tomcat. The above mentioned
four jobs continue to run.

If I end the submitted TOMCATJOB using ENDJOB, all jobs end except for
QP0ZSPWT which appears to be running the JVM for Tomcat. There seems to be
no way to be able to identify this job so that it can be ended from a
program with ENDJOB, (other than by creating your own subsystem and setting
this job as a prestart job in the subsystem and ending the entire subsystem,
as suggested by the manual). (Unfortunately, the QP0ZSPWT job holds the
Tomcat ports open and so any subsequent submission will conflict.)

All thoughts appreciated.

Chris Jewell