I've had on my to-do list for a while to implement a transparent cache for LWP::UserAgent, because I've run across similar things to you.

But instead of doing that, you could also just set up Apache's mod_proxy to be a caching proxy, and then point your UserAgent's proxy settings at your apache server. That'd effectively be the same thing.

-- Randal L. Schwartz, Perl hacker
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