Intermittent problems accessing MySQL data

I have inherited a site written in perl.  Recently an intermittent 
problem has come up and when users log into the site, they end up seeing 
other users data.  I personally can not reproduce the problem but it has 
happened enough that I am sure it is more than just a fluke.  Does 
anyone know of any recent changes in perl that could cause this kind of 
problem?  The site is pretty old, I would guess at least 5 years or more 
since it was written.  However the problem has only happened in the last 
few months.  I have no control over the server and am told that updates 
are applied automatically. 

BTW I haven't used perl in years so unless someone here has a pretty 
good idea what to look for, I will most likely be redoing it in php.

-- 
Chris W
KE5GIX

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