SVNAnt and auto jarring?

Hi all,

I am not sure if svnant is the right tool for my system, so I thought I'd ask.
I have a rather large web application running in WebLogic/WebSphere.
This thing is
not actually my project, but the hosting of the app is. I get updates
and customizations to the
app from the developer and I keep a current extracted .ear of the app
in subversion to make
sure there is no ambiguity in the versions of jars in the ear. Also,
I sometimes have to clean up xml files from the vendor and need to
keep such things versioned for sanity.
My problem is this: I have more than one admin who updates the ear.
With subversion they can
do it remotely or on the server. The problem is that they may have to
extract a jar that is in the
ear to do an update. Here's the process they follow:

# jar xvf elms.ear
(this creates the entire first-level structure of jars and the war)
# mkdir elms_custom_jar
#cp elms_custom.jar elms_custom_jar
#cd elms_custom_jar
#jar xvf elms_custom.jar
#rm -f elms_custom.jar
#cd ..
#svn add elms_custom_jar; svn commit -m "Committing new extraction."
(this step only occurs if this jar was never extracted for update before)
(Next they would put the updates into the jar and commit again)
#cd elms_custom_jar
#jar uvf ../elms_custom.jar <path of whatever was updated in this jar>
#cd ..
#jar uvf elms.ear elms_custom.jar

THen the ear is ready to be redeployed.
What I want to do is allow a user to check this out to their machine,
update the ear structure or files and then commit. Then I would want
svnant, or some other tool, to judge by either svn props or date what
has been updated and rejar the affected jars and then the ear.

Is this possible or am I looking at a possible candidate for perl?

-- 
Regards,
Bryan Simmons
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 Always code as if the guy who ends up maintaining your code will 
 be a violent psychopath who knows where you live.
   -- Rick Osborne
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