I've written explanations with sample code and workarounds on the Class::DBI mailing list and the mod_perl list.
Considering the importance of this topic, why not post that here on Perlmonks - it would make a good tutorial.

In reply to Re^2: DBI::connect_cached, Apache::DBI and Class::DBI by Arunbear
in thread DBI::connect_cached, Apache::DBI and Class::DBI by johnnywang

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