CGI::Simple uses SelfLoader to avoid compiling methods that are rarely used. You do this by placing these methods below a __DATA__ token. At compile time compilation stops at the __DATA__ token.
I didn't notice this part at first. mod_perl scripts cannot contain __DATA__ tokens. Do you have a solution for this? I suppose you can make a separate mod_perl implmentation without the __DATA__ token. Since the performance issue you're resolving is load time, this really doesn't apply in this instance. However, then you have CGI::Simple, CGI::Simple::Standard, and CGI::Simple::mod_perl. I don't see a problem with that if you really need those namespaces to address these issues, but I wonder if others would object.
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